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Python | Rust | |||
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1 |
Print a literal string on standard output
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2 |
Loop to execute some code a constant number of times
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3 |
Like a function which doesn't return any value, thus has only side effects (e.g. Print to standard output)
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4 |
Create a function which returns the square of an integer
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5 |
Declare a container type for two floating-point numbers x and y
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6 |
Do something with each item x of the list (or array) items, regardless indexes.
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7 |
Print each index i with its value x from an array-like collection items
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8 |
Create a new map object x, and provide some (key, value) pairs as initial content.
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9 |
The structure must be recursive because left child and right child are binary trees too. A node has access to children nodes, but not to its parent.
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10 |
Generate a random permutation of the elements of list x
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11 |
The list x must be non-empty.
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12 |
Check if the list contains the value x.
list is an iterable finite container. |
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13 |
Access each key k with its value x from an associative array mymap, and print them.
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14 |
Pick a random number greater than or equals to a, strictly inferior to b. Precondition : a < b.
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15 |
Pick a random integer greater than or equals to a, inferior or equals to b. Precondition : a < b.
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16 |
Call a function f on every node of binary tree bt, in depth-first infix order
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17 |
The structure must be recursive. A node may have zero or more children. A node has access to its children nodes, but not to its parent.
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18 |
Call a function f on every node of a tree, in depth-first prefix order
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19 |
Reverse the order of the elements of the list x.
This may reverse "in-place" and destroy the original ordering. |
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20 |
Implement a function search which looks for item x in a 2D matrix m.
Return indices i, j of the matching cell. Think of the most idiomatic way in the language to return the two values at the same time. |
Alternative implementation:
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21 |
Swap the values of the variables a and b
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22 |
Extract the integer value i from its string representation s (in radix 10)
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23 |
Given a real number x, create its string representation s with 2 decimal digits following the dot.
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24 |
Declare a new string s and initialize it with the literal value "ネコ" (which means "cat" in japanese)
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25 |
Share the string value "Alan" with an existing running process which will then display "Hello, Alan"
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26 |
Declare and initialize a matrix x having m rows and n columns, containing real numbers.
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27 |
Declare and initialize a 3D array x, having dimensions boundaries m, n, p, and containing real numbers.
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Alternative implementation:
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28 |
Sort the elements of the list (or array-like collection) items in ascending order of x.p, where p is a field of the type Item of the objects in items.
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29 |
Remove i-th item from list items.
This will alter the original list or return a new list, depending on which is more idiomatic. Note that in most languages, the smallest valid value for i is 0. |
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30 |
Launch the concurrent execution of the procedure f with parameter i from 1 to 1000.
Tasks are independent and f(i) doesn't return any value. Tasks need not run all at the same time, so you may use a pool. |
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31 |
Create the recursive function f which returns the factorial of the non-negative integer i, calculated from f(i-1)
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32 |
Create function exp which calculates (fast) the value x power n.
x and n are non-negative integers. |
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33 |
Assign to the variable x the new value f(x), making sure that no other thread may modify x between the read and the write.
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34 |
Declare and initialize a set x containing unique objects of type T.
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Alternative implementation:
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35 |
Implement a function compose (A -> C) with parameters f (A -> B) and g (B -> C), which returns the composition function g ∘ f
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Alternative implementation:
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36 |
Implement a function compose which returns composition function g ∘ f for any functions f and g having exactly 1 parameter.
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Alternative implementation:
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37 |
Transform a function that takes multiple arguments into a function for which some of the arguments are preset.
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38 |
Find substring t consisting in characters i (included) to j (excluded) of string s.
Character indices start at 0 unless specified otherwise. Make sure that multibyte characters are properly handled. |
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Alternative implementation:
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39 |
Set the boolean ok to true if the string word is contained in string s as a substring, or to false otherwise.
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40 |
Declare a Graph data structure in which each Vertex has a collection of its neighbouring vertices.
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41 |
Create the string t containing the same characters as the string s, in reverse order.
The original string s must remain unaltered. Each character must be handled correctly regardless its number of bytes in memory. |
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42 |
Print each item v of list a which is not contained in list b.
For this, write an outer loop to iterate on a and an inner loop to iterate on b. |
Alternative implementation:
Alternative implementation:
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43 |
Look for a negative value v in 2D integer matrix m. Print it and stop searching.
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Alternative implementation:
Alternative implementation:
Alternative implementation:
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44 |
Insert the element x at position i in the list s. Further elements must be shifted to the right.
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45 |
Sleep for 5 seconds in current thread, before proceeding with the next instructions.
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46 |
Create the string t consisting of the 5 first characters of the string s.
Make sure that multibyte characters are properly handled. |
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47 |
Create string t consisting in the 5 last characters of string s.
Make sure that multibyte characters are properly handled. |
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Alternative implementation:
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48 |
Assign to variable s a string literal consisting in several lines of text, including newlines.
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49 |
Build list chunks consisting in substrings of the string s, separated by one or more space characters.
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50 |
Write a loop that has no end clause.
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51 |
Determine whether the map m contains an entry for the key k
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52 |
Determine whether the map m contains an entry with the value v, for some key.
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Alternative implementation:
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53 |
Concatenate elements of string list x joined by the separator ", " to create a single string y.
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54 |
Calculate the sum s of the integer list or array x.
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55 |
Create the string representation s (in radix 10) of the integer value i.
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56 |
Fork-join : launch the concurrent execution of procedure f with parameter i from 1 to 1000.
Tasks are independent and f(i) doesn't return any value. Tasks need not run all at the same time, so you may use a pool. Wait for the completion of the 1000 tasks and then print "Finished". |
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57 |
Create the list y containing the items from the list x that satisfy the predicate p. Respect the original ordering. Don't modify x in-place.
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58 |
Create the string lines from the content of the file with filename f.
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59 |
Print the message "x is negative" to standard error (stderr), with integer x value substitution (e.g. "-2 is negative").
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60 |
Assign to x the string value of the first command line parameter, after the program name.
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61 |
Assign to the variable d the current date/time value, in the most standard type.
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62 |
Set i to the first position of string y inside string x, if exists.
Specify if i should be regarded as a character index or as a byte index. Explain the behavior when y is not contained in x. |
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63 |
Assign to x2 the value of string x with all occurrences of y replaced by z.
Assume occurrences of y are not overlapping. |
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64 |
Assign to x the value 3^247
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65 |
From the real value x in [0,1], create its percentage string representation s with one digit after decimal point. E.g. 0.15625 -> "15.6%"
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66 |
Calculate the result z of x power n, where x is a big integer and n is a positive integer.
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67 |
Calculate binom(n, k) = n! / (k! * (n-k)!). Use an integer type able to handle huge numbers.
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68 |
Create an object x to store n bits (n being potentially large).
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69 |
Use seed s to initialize a random generator.
If s is constant, the generator output will be the same each time the program runs. If s is based on the current value of the system clock, the generator output will be different each time. |
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70 |
Get the current datetime and provide it as a seed to a random generator. The generator sequence will be different at each run.
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71 |
Basic implementation of the Echo program: Print all arguments except the program name, separated by space, followed by newline.
The idiom demonstrates how to skip the first argument if necessary, concatenate arguments as strings, append newline and print it to stdout. |
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73 |
Create a factory named fact for any sub class of Parent and taking exactly one string str as constructor parameter.
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74 |
Compute the greatest common divisor x of big integers a and b. Use an integer type able to handle huge numbers.
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75 |
Compute the least common multiple x of big integers a and b. Use an integer type able to handle huge numbers.
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76 |
Create the string s of integer x written in base 2.
E.g. 13 -> "1101" |
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77 |
Declare a complex x and initialize it with value (3i - 2). Then multiply it by i.
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78 |
Execute a block once, then execute it again as long as boolean condition c is true.
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79 |
Declare the floating point number y and initialize it with the value of the integer x .
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80 |
Declare integer y and initialize it with the value of floating point number x . Ignore non-integer digits of x .
Make sure to truncate towards zero: a negative x must yield the closest greater integer (not lesser). |
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81 |
Declare the integer y and initialize it with the rounded value of the floating point number x .
Ties (when the fractional part of x is exactly .5) must be rounded up (to positive infinity). |
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82 |
Find how many times string s contains substring t.
Specify if overlapping occurrences are counted. |
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83 |
Declare the regular expression r matching the strings "http", "htttp", "httttp", etc.
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84 |
Count number c of 1s in the integer i in base 2.
E.g. i=6 → c=2 |
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85 |
Write boolean function addingWillOverflow which takes two integers x, y and return true if (x+y) overflows.
An overflow may be above the max positive value, or below the min negative value. |
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86 |
Write the boolean function multiplyWillOverflow which takes two integers x, y and returns true if (x*y) overflows.
An overflow may reach above the max positive value, or below the min negative value. |
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87 |
Exit immediately.
If some extra cleanup work is executed by the program runtime (not by the OS itself), describe it. |
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88 |
Create a new bytes buffer buf of size 1,000,000.
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89 |
You've detected that the integer value of argument x passed to the current function is invalid. Write the idiomatic way to abort the function execution and signal the problem.
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90 |
Expose a read-only integer x to the outside world while being writable inside a structure or a class Foo.
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91 |
Read from the file data.json and write its content into the object x.
Assume the JSON data is suitable for the type of x. |
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92 |
Write the contents of the object x into the file data.json.
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93 |
Implement the procedure control which receives one parameter f, and runs f.
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94 |
Print the name of the type of x. Explain if it is a static type or dynamic type.
This may not make sense in all languages. |
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95 |
Assign to variable x the length (number of bytes) of the local file at path.
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96 |
Set the boolean b to true if string s starts with prefix prefix, false otherwise.
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97 |
Set boolean b to true if string s ends with string suffix, false otherwise.
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98 |
Convert a timestamp ts (number of seconds in epoch-time) to a date with time d. E.g. 0 -> 1970-01-01 00:00:00
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99 |
Assign to the string x the value of the fields (year, month, day) of the date d, in format YYYY-MM-DD.
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100 |
Sort elements of array-like collection items, using a comparator c.
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101 |
Make an HTTP request with method GET to the URL u, then store the body of the response in the string s.
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Alternative implementation:
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102 |
Make an HTTP request with method GET to the URL u, then store the body of the response in the file result.txt. Try to save the data as it arrives if possible, without having all its content in memory at once.
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Alternative implementation:
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103 |
Read from the file data.xml and write its contents into the object x.
Assume the XML data is suitable for the type of x. |
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105 |
1
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106 |
Assign to string dir the path of the working directory.
(This is not necessarily the folder containing the executable itself) |
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107 |
Assign to string dir the path of the folder containing the currently running executable.
(This is not necessarily the working directory, though.) |
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108 |
Print the value of variable x, but only if x has been declared in this program.
This makes sense in some languages, not all of them. (Null values are not the point, rather the very existence of the variable.) |
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109 |
Set n to the number of bytes of a variable t (of type T).
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110 |
Set the boolean blank to true if the string s is empty, or null, or contains only whitespace ; false otherwise.
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111 |
From current process, run program x with command-line parameters "a", "b".
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Alternative implementation:
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112 |
Print each key k with its value x from an associative array mymap, in ascending order of k.
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113 |
Print each key k with its value x from an associative array mymap, in ascending order of x.
Multiple entries may exist for the same value x. |
Alternative implementation:
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114 |
Set boolean b to true if objects x and y contain the same values, recursively comparing all referenced elements in x and y.
Tell if the code correctly handles recursive types. |
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115 |
Set boolean b to true if date d1 is strictly before date d2 ; false otherwise.
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116 |
Remove all occurrences of string w from string s1, and store the result in s2.
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117 |
Set n to the number of elements of the list x.
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118 |
Create the set y from the list x.
x may contain duplicates. y is unordered and has no repeated values. |
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119 |
Remove duplicates from the list x.
Explain if the original order is preserved. |
Alternative implementation:
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120 |
Read an integer value from the standard input into the variable n
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Alternative implementation:
Alternative implementation:
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121 |
Listen UDP traffic on port p and read 1024 bytes into the buffer b.
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122 |
Create an enumerated type Suit with 4 possible values SPADES, HEARTS, DIAMONDS, CLUBS.
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123 |
Verify that predicate isConsistent returns true, otherwise report assertion violation.
Explain if the assertion is executed even in production environment or not. |
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124 |
Write the function binarySearch which returns the index of an element having the value x in the sorted array a, or -1 if no such element exists.
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125 |
measure the duration t, in nanoseconds, of a call to the function foo. Print this duration.
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126 |
Write a function foo that returns a string and a boolean value.
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127 |
Import the source code for the function foo body from a file "foobody.txt".
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128 |
Call a function f on every node of a tree, in breadth-first prefix order
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129 |
Call the function f on every vertex accessible from the vertex start, in breadth-first prefix order
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130 |
Call th function f on every vertex accessible from the vertex v, in depth-first prefix order
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131 |
Execute f1 if condition c1 is true, or else f2 if condition c2 is true, or else f3 if condition c3 is true.
Don't evaluate a condition when a previous condition was true. |
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132 |
Run the procedure f, and return the duration of the execution of f.
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133 |
Set boolean ok to true if string word is contained in string s as a substring, even if the case doesn't match, or to false otherwise.
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Alternative implementation:
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134 |
Declare and initialize a new list items, containing 3 elements a, b, c.
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135 |
Remove at most 1 item from list items, having the value x.
This will alter the original list or return a new list, depending on which is more idiomatic. If there are several occurrences of x in items, remove only one of them. If x is absent, keep items unchanged. |
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136 |
Remove all occurrences of the value x from list items.
This will alter the original list or return a new list, depending on which is more idiomatic. |
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137 |
Set the boolean b to true if the string s contains only characters in the range '0'..'9', false otherwise.
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138 |
Create a new temporary file on the filesystem.
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139 |
Create a new temporary folder on filesystem, for writing.
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140 |
Delete from map m the entry having key k.
Explain what happens if k is not an existing key in m. |
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141 |
Iterate in sequence over the elements of the list items1 then items2. For each iteration print the element.
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142 |
Assign to string s the hexadecimal representation (base 16) of integer x.
E.g. 999 -> "3e7" |
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143 |
Iterate alternatively over the elements of the lists items1 and items2. For each iteration, print the element.
Explain what happens if items1 and items2 have different size. |
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144 |
Set boolean b to true if file at path fp exists on filesystem; false otherwise.
Beware that you should not do this and then in the next instruction assume the result is still valid, this is a race condition on any multitasking OS. |
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145 |
Print message msg, prepended by current date and time.
Explain what behavior is idiomatic: to stdout or stderr, and what the date format is. |
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146 |
Extract floating point value f from its string representation s
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147 |
Create string t from string s, keeping only ASCII characters
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148 |
Read a list of integer numbers from the standard input, until EOF.
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150 |
Remove the last character from the string p, if this character is a forward slash /
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151 |
Remove last character from string p, if this character is the file path separator of current platform.
Note that this also transforms unix root path "/" into the empty string! |
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152 |
Create string s containing only the character c.
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153 |
Create the string t as the concatenation of the string s and the integer i.
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154 |
Find color c, the average between colors c1, c2.
c, c1, c2 are strings of hex color codes: 7 chars, beginning with a number sign # . Assume linear computations, ignore gamma corrections. |
Alternative implementation:
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155 |
Delete from filesystem the file having path filepath.
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156 |
Assign to the string s the value of the integer i in 3 decimal digits. Pad with zeros if i < 100. Keep all digits if i ≥ 1000.
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157 |
Initialize a constant planet with string value "Earth".
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158 |
Create a new list y from randomly picking exactly k elements from list x.
It is assumed that x has at least k elements. Each element must have same probability to be picked. Each element from x must be picked at most once. Explain if the original ordering is preserved or not. |
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159 |
Define a Trie data structure, where entries have an associated value.
(Not all nodes are entries) |
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160 |
Execute f32() if platform is 32-bit, or f64() if platform is 64-bit.
This can be either a compile-time condition (depending on target) or a runtime detection. |
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Alternative implementation:
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161 |
Multiply all the elements of the list elements by a constant c
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162 |
execute bat if b is a program option and fox if f is a program option.
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Alternative implementation:
Alternative implementation:
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163 |
Print all the list elements, two by two, assuming list length is even.
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Alternative implementation:
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164 |
Open the URL s in the default browser.
Set the boolean b to indicate whether the operation was successful. |
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165 |
Assign to the variable x the last element of the list items.
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166 |
Create the list ab containing all the elements of the list a, followed by all the elements of the list b.
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167 |
Create the string t consisting of the string s with its prefix p removed (if s starts with p).
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168 |
Create string t consisting of string s with its suffix w removed (if s ends with w).
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169 |
Assign to the integer n the number of characters of the string s.
Make sure that multibyte characters are properly handled. n can be different from the number of bytes of s. |
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170 |
Set n to the number of elements stored in mymap.
This is not always equal to the map capacity. |
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171 |
Append the element x to the list s.
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172 |
Insert value v for key k in map m.
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173 |
Number will be formatted with a comma separator between every group of thousands.
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174 |
Make a HTTP request with method POST to the URL u
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175 |
From the array a of n bytes, build the equivalent hex string s of 2n digits.
Each byte (256 possible values) is encoded as two hexadecimal characters (16 possible values per digit). |
Alternative implementation:
Alternative implementation:
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176 |
From hex string s of 2n digits, build the equivalent array a of n bytes.
Each pair of hexadecimal characters (16 possible values per digit) is decoded into one byte (256 possible values). |
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177 |
Construct a list L that contains all filenames that have the extension ".jpg" , ".jpeg" or ".png" in directory D and all its subdirectories.
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Alternative implementation:
Alternative implementation:
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178 |
Set boolean b to true if if the point with coordinates (x,y) is inside the rectangle with coordinates (x1,y1,x2,y2) , or to false otherwise.
Describe if the edges are considered to be inside the rectangle. |
Alternative implementation:
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179 |
Return the center c of the rectangle with coördinates(x1,y1,x2,y2)
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Alternative implementation:
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180 |
Create the list x containing the contents of the directory d.
x may contain files and subfolders. No recursive subfolder listing. |
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182 |
Output the source of the current program. A quine is a computer program that takes no input and produces a copy of its own source code as its only output.
Reading the source file from disk is cheating. |
Alternative implementation:
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183 |
Make a HTTP request with method PUT to the URL u
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184 |
Assign to t a string representing the day, month and year of the day after the current date.
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185 |
Schedule the execution of f(42) in 30 seconds.
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186 |
Exit a program cleanly indicating no error to OS
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187 |
Disjoint Sets hold elements that are partitioned into a number of disjoint (non-overlapping) sets.
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188 |
Perform matrix multiplication of a real matrix a with nx rows and ny columns, a real matrix b with ny rows and nz columns and assign the value to a real matrix c with nx rows and nz columns.
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189 |
Produce a new list y containing the result of the function T applied to all elements e of the list x that match the predicate P.
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190 |
Declare an external C function with the prototype
void foo(double *a, int n); and call it, passing an array (or a list) of size 10 to a and 10 to n. Use only standard features of your language. |
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191 |
Given a one-dimensional array a, check if any value is larger than x, and execute the procedure f if that is the case
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192 |
Declare a real variable a with at least 20 digits; if the type does not exist, issue an error at compile time.
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193 |
Declare two two-dimensional arrays a and b of dimension n*m and m*n, respectively. Assign to b the transpose of a (i.e. the value with index interchange).
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194 |
Given an array a, set b to an array which has the values of a along its second dimension shifted by n. Elements shifted out should come back at the other end.
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195 |
Pass an array a of real numbers to the procedure (resp. function) foo. Output the size of the array, and the sum of all its elements when each element is multiplied with the array indices i and j (assuming they start from one).
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Alternative implementation:
Alternative implementation:
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196 |
Given an integer array a of size n, pass the first, third, fifth and seventh, ... up to the m th element to a routine foo which sets all these elements to 42.
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Alternative implementation:
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197 |
Retrieve the contents of file at path into a list of strings lines, in which each element is a line of the file.
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198 |
Abort program execution with error condition x (where x is an integer value)
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199 |
Truncate a file F at the given file position.
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200 |
Compute the hypotenuse h of the triangle where the sides adjacent to the square angle have lengths x and y.
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201 |
Calculate n, the Euclidean norm of data, where data is a list of floating point values.
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202 |
Calculate the sum of squares s of data, an array of floating point values.
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203 |
Calculate the mean m and the standard deviation s of the list of floating point values data.
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204 |
Given a real number a, print the fractional part and the exponent of the internal representation of that number. For 3.14, this should print (approximately)
0.785 2 |
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205 |
Read an environment variable with the name "FOO" and assign it to the string variable foo. If it does not exist or if the system does not support environment variables, assign a value of "none".
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Alternative implementation:
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206 |
Execute different procedures foo, bar, baz and barfl if the string str contains the name of the respective procedure. Do it in a way natural to the language.
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Alternative implementation:
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207 |
Allocate a list a containing n elements (n assumed to be too large for a stack) that is automatically deallocated when the program exits the scope it is declared in.
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208 |
Given the arrays a,b,c,d of equal length and the scalar e, calculate a = e*(a+b*c+cos(d)).
Store the results in a. |
Alternative implementation:
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209 |
Declare a type t which contains a string s and an integer array n with variable size, and allocate a variable v of type t. Allocate v.s and v.n and set them to the values "Hello, world!" for s and [1,4,9,16,25], respectively. Deallocate v, automatically deallocating v.s and v.n (no memory leaks).
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210 |
Assign, at runtime, the compiler version and the options the program was compiled with to variables version and options, respectively, and print them. For interpreted languages, substitute the version of the interpreter.
Example output: GCC version 10.0.0 20190914 (experimental) -mtune=generic -march=x86-64 |
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211 |
Create the folder at path on the filesystem
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212 |
Set the boolean b to true if path exists on the filesystem and is a directory; false otherwise.
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213 |
Compare four strings in pair-wise variations. The string comparison can be implemented with an equality test or a containment test, must be case-insensitive and must apply Unicode casefolding.
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214 |
Append extra character c at the end of string s to make sure its length is at least m.
The length is the number of characters, not the number of bytes. |
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215 |
Prepend extra character c at the beginning of string s to make sure its length is at least m.
The length is the number of characters, not the number of bytes. |
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216 |
Add the extra character c at the beginning and ending of string s to make sure its length is at least m.
After the padding the original content of s should be at the center of the result. The length is the number of characters, not the number of bytes. E.g. with s="abcd", m=10 and c="X" the result should be "XXXabcdXXX". |
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217 |
Create a zip-file with filename name and add the files listed in list to that zip-file.
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Alternative implementation:
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218 |
Create the list c containing all unique elements that are contained in both lists a and b.
c should not contain any duplicates, even if a and b do. The order of c doesn't matter. |
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219 |
Create the string t from the value of string s with each sequence of spaces replaced by a single space.
Explain if only the space characters will be replaced, or the other whitespaces as well: tabs, newlines. |
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220 |
Create t consisting of 3 values having different types.
Explain if the elements of t are strongly typed or not. |
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221 |
Create string t from string s, keeping only digit characters 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.
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222 |
Set i to the first index in list items at which the element x can be found, or -1 if items does not contain x.
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223 |
Loop through list items checking a condition. Do something else if no matches are found.
A typical use case is looping through a series of containers looking for one that matches a condition. If found, an item is inserted; otherwise, a new container is created. These are mostly used as an inner nested loop, and in a location where refactoring inner logic into a separate function reduces clarity. |
Alternative implementation:
Alternative implementation:
Alternative implementation:
Alternative implementation:
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224 |
Insert the element x at the beginning of the list items.
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225 |
Declare an optional integer argument x to procedure f, printing out "Present" and its value if it is present, "Not present" otherwise
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226 |
Remove the last element from the list items.
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227 |
Create the new list y containing the same elements as the list x.
Subsequent modifications of y must not affect x (except for the contents referenced by the elements themselves if they contain pointers). |
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228 |
Copy the file at path src to dst.
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230 |
Cancel an ongoing processing p if it has not finished after 5s.
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231 |
Set b to true if the byte sequence s consists entirely of valid UTF-8 character code points, false otherwise.
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232 |
Print "verbose is true" if the flag -v was passed to the program command line, "verbose is false" otherwise.
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233 |
Print the value of the flag -country passed to the program command line, or the default value "Canada" if no such flag was passed.
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Alternative implementation:
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234 |
Assign to the string s the standard base64 encoding of the byte array data, as specified by RFC 4648.
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235 |
Assign to byte array data the bytes represented by the base64 string s, as specified by RFC 4648.
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236 |
Initialize a quotient q = a/b of arbitrary precision. a and b are large integers.
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237 |
Assign to c the result of (a xor b)
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238 |
Write in a new byte array c the xor result of byte arrays a and b.
a and b have the same size. |
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239 |
Assign to string x the first word of string s consisting of exactly 3 digits, or the empty string if no such match exists.
A word containing more digits, or 3 digits as a substring fragment, must not match. |
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240 |
Lists a and b have the same length. Apply the same permutation to a and b to have them sorted based on the values of a.
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241 |
Explicitly decrease the priority of the current process, so that other execution threads have a better chance to execute now. Then resume normal execution and call the function busywork.
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242 |
Call a function f on each element e of a set x.
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243 |
Print the contents of the list or array a on the standard output.
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244 |
Print the contents of the map m to the standard output: keys and values.
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245 |
Print the value of object x having custom type T, for log or debug.
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246 |
Set c to the number of distinct elements in the list items.
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Alternative implementation:
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247 |
Remove all the elements from list x that don't satisfy the predicate p, without allocating a new list.
Keep all the elements that do satisfy p. For languages that don't have mutable lists, refer to idiom #57 instead. |
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248 |
Construct the "double precision" (64-bit) floating point number d from the mantissa m, the exponent e and the sign flag s (true means the sign is negative).
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249 |
Define variables a, b and c in a concise way.
Explain if they need to have the same type. |
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250 |
Choose a value x from map m.
m must not be empty. Ignore the keys. |
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251 |
Extract integer value i from its binary string representation s (in radix 2)
E.g. "1101" -> 13 |
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252 |
Assign to the variable x the string value "a" if calling the function condition returns true, or the value "b" otherwise.
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253 |
Print the stack frames of the current execution thread of the program.
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254 |
Replace all exact occurrences of "foo" with "bar" in the string list x
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255 |
Print the values of the set x to the standard output.
The order of the elements is irrelevant and is not required to remain the same next time. |
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256 |
Print the numbers 5, 4, ..., 0 (included), one line per number.
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257 |
Print each index i and value x from the list items, from the last down to the first.
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Alternative implementation:
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258 |
Convert the string values from list a into a list of integers b.
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259 |
Build the list parts consisting of substrings of the input string s, separated by any of the characters ',' (comma), '-' (dash), '_' (underscore).
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260 |
Declare a new list items of string elements, containing zero elements
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261 |
Assign to the string x the value of fields (hours, minutes, seconds) of the date d, in format HH:MM:SS.
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262 |
Assign to t the number of trailing 0 bits in the binary representation of the integer n.
E.g. for n=112, n is 1110000 in base 2 ⇒ t=4 |
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263 |
Write two functions log2d and log2u, which calculate the binary logarithm of their argument n rounded down and up, respectively. n is assumed to be positive. Print the result of these functions for numbers from 1 to 12.
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Alternative implementation:
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264 |
Pass a two-dimensional integer array a to a procedure foo and print the size of the array in each dimension. Do not pass the bounds manually. Call the procedure with a two-dimensional array.
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Alternative implementation:
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265 |
Calculate the parity p of the integer variable i : 0 if it contains an even number of bits set, 1 if it contains an odd number of bits set.
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266 |
Assign to the string s the value of the string v repeated n times, and write it out.
E.g. v="abc", n=5 ⇒ s="abcabcabcabcabc" |
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267 |
Declare an argument x to a procedure foo that can be of any type. If the type of the argument is a string, print it, otherwise print "Nothing."
Test by passing "Hello, world!" and 42 to the procedure. |
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268 |
Define a type vector containing three floating point numbers x, y, and z. Write a user-defined operator x that calculates the cross product of two vectors a and b.
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Alternative implementation:
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269 |
Given the enumerated type t with 3 possible values: bike, car, horse.
Set the enum value e to one of the allowed values of t. Set the string s to hold the string representation of e (so, not the ordinal value). Print s. |
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270 |
Given a floating point number r1 classify it as follows:
If it is a signaling NaN, print "This is a signaling NaN." If it is a quiet NaN, print "This s a quiet NaN." If it is not a NaN, print "This is a number." |
Alternative implementation:
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271 |
If a variable x passed to procedure tst is of type foo, print "Same type." If it is of a type that extends foo, print "Extends type." If it is neither, print "Not related."
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272 |
Fizz buzz is a children's counting game, and a trivial programming task used to affirm that a programmer knows the basics of a language: loops, conditions and I/O.
The typical fizz buzz game is to count from 1 to 100, saying each number in turn. When the number is divisible by 3, instead say "Fizz". When the number is divisible by 5, instead say "Buzz". When the number is divisible by both 3 and 5, say "FizzBuzz" |
Alternative implementation:
Alternative implementation:
Alternative implementation:
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273 |
Set the boolean b to true if the directory at filepath p is empty (i.e. doesn't contain any other files and directories)
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274 |
Create the string t from the string s, removing all the spaces, newlines, tabulations, etc.
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275 |
From the string s consisting of 8n binary digit characters ('0' or '1'), build the equivalent array a of n bytes.
Each chunk of 8 binary digits (2 possible values per digit) is decoded into one byte (256 possible values). |
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276 |
Insert an element e into the set x.
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277 |
Remove the element e from the set x.
Explains what happens if e was already absent from x. |
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278 |
Read one line into the string line.
Explain what happens if EOF is reached. |
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279 |
Read all the lines (until EOF) into the list of strings lines.
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280 |
Remove all the elements from the map m that don't satisfy the predicate p.
Keep all the elements that do satisfy p. Explain if the filtering happens in-place, i.e. if m is reused or if a new map is created. |
|
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281 |
You have a Point with integer coordinates x and y. Create a map m with key type Point (or equivalent) and value type string. Insert "Hello" at position (42, 5).
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Alternative implementation:
Alternative implementation:
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282 |
Declare a type Foo, and create a new map with Foo as key type.
Mention the conditions on Foo required to make it a possible map key type. |
|
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283 |
Build the list parts consisting of substrings of input string s, separated by the string sep.
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284 |
Create a new list a (or array, or slice) of size n, where all elements are integers initialized with the value 0.
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285 |
Given two floating point variables a and b, set a to a to a quiet NaN and b to a signalling NaN. Use standard features of the language only, without invoking undefined behavior.
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286 |
Print a line "Char i is c" for each character c of the string s, where i is the character index of c in s (not the byte index).
Make sure that multi-byte characters are properly handled, and count for a single character. |
Alternative implementation:
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287 |
Assign to n the number of bytes in the string s.
This can be different from the number of characters. If n includes more bytes than the characters per se (trailing zero, length field, etc.) then explain it. One byte is 8 bits. |
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288 |
Set the boolean b to true if the set x contains the element e, false otherwise.
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289 |
Create the string s by concatenating the strings a and b.
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290 |
Sort the part of the list items from index i (included) to index j (excluded), in place, using the comparator c.
Elements before i and after j must remain unchanged. |
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291 |
Delete all the elements from index i (included) to index j (excluded) from the list items.
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|
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292 |
Write "Hello World and 你好" to standard output in UTF-8.
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293 |
Create a new stack s, push an element x, then pop the element into the variable y.
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|||
294 |
Given an array a containing the three values 1, 12, 42, print out
"1, 12, 42" with a comma and a space after each integer except the last one. |
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295 |
Given the enumerated type T, create a function TryStrToEnum that takes a string s as input and converts it into an enum value of type T.
Explain whether the conversion is case sensitive or not. Explain what happens if the conversion fails. |
|
||
296 |
Assign to x2 the value of string x with the last occurrence of y replaced by z.
If y is not contained in x, then x2 has the same value as x. |
|
||
297 |
Sort the string list data in a case-insensitive manner.
The sorting must not destroy the original casing of the strings. |
|||
298 |
Create the map y by cloning the map x.
y is a shallow copy, not a deep copy. |
|
||
299 |
Write a line of comments.
This line will not be compiled or executed. |
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301 |
Compute the Fibonacci sequence of n numbers using recursion.
Note that naive recursion is extremely inefficient for this task. |
|
||
302 |
Given the integer x = 8, assign to the string s the value "Our sun has 8 planets", where the number 8 was evaluated from x.
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|
||
303 |
Declare an array a of integers with six elements, where the first index is 42 and consecutive elements have the indices 43, 44, 45, 46, 47.
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|
||
304 |
Create the array of bytes data by encoding the string s in UTF-8.
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|
305 |
Compute and print a^b, and a^n, where a and b are floating point numbers and n is an integer.
|
|||
306 |
Preallocate memory in the list x for a minimum total capacity of 200 elements.
This is not possible in all languages. It is only meant as a performance optimization, should not change the length of x, and should not have any effect on correctness. |
|
||
307 |
Create a function that XOR encrypts/decrypts a string
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|
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308 |
Create the string representation s of the integer value n in base b.
18 in base 3 -> "200" 26 in base 5 -> "101" 121 in base 12 -> "a1" |
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309 |
Create the new 2-dimensional array y containing a copy of the elements of the 2-dimensional array x.
x and y must not share memory. Subsequent modifications of y must not affect x. |
|
||
310 |
Fill the byte array a with randomly generated bytes.
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|
||
311 |
Create the new object y by cloning the all the contents of x, recursively.
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|
||
312 |
Set b to true if the lists p and q have the same size and the same elements, false otherwise.
|
|||
313 |
Set b to true if the maps m and n have the same key/value entries, false otherwise.
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|
||
314 |
Set all the elements in the array x to the same value v
|
|||
315 |
Given any function f, create an object or function m that stores the results of f, and calls f only on inputs for which the result is not stored yet.
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|
||
316 |
Determine the number c of elements in the list x that satisfy the predicate p.
|
|||
317 |
Create a string s of n characters having uniform random values out of the 62 alphanumeric values A-Z, a-z, 0-9
|
|
||
318 |
Assign to the integer x a random number between 0 and 17 (inclusive), from a crypto secure random number generator.
|
|||
319 |
Write a function g that behaves like an iterator.
Explain if it can be used directly in a for loop. |
|
||
320 |
Set b to true if the string s is empty, false otherwise
|
|||
321 |
Assign to c the value of the i-th character of the string s.
Make sure to properly handle multi-byte characters. i is the character index, which may not be equal to the byte index. |
|
||
322 |
|
|||
323 |
Make an HTTP request with method GET to the URL u, with the request header "accept-encoding: gzip", then store the body of the response in the buffer data.
|
|
||
324 |
Set the string c to the (first) value of the header "cache-control" of the HTTP response res.
|
|
||
325 |
Create a new queue q, then enqueue two elements x and y, then dequeue an element into the variable z.
|
|
||
326 |
Assign to t the number of milliseconds elapsed since 00:00:00 UTC on 1 January 1970.
|
|
||
327 |
Assign to t the value of the string s, with all letters mapped to their lower case.
|
|
||
328 |
Assign to t the value of the string s, with all letters mapped to their upper case.
|
|
||
329 |
Assign to v the value stored in the map m for the key k.
Explain what happens if there is no entry for k in m. |
|||
330 |
Create the list a containing all the values of the map m.
Ignore the keys of m. The order of a doesn't matter. a may contain duplicate values. |
|
||
331 |
Remove all entries from the map m.
Explain if other references to the same map now see an empty map as well. |
|||
332 |
Create the list k containing all the keys of the map m
|
|||
333 |
Print the object x in human-friendly JSON format, with newlines and indentation.
|
|
||
334 |
Create the new map c containing all of the (key, value) entries of the two maps a and b.
Explain what happens for keys existing in both a and b. |
|
||
335 |
Create the map m containing all the elements e of the list a, using as key the field e.id.
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|
||
336 |
Compute x = b ⁿ
b raised to the power of n is equal to the product of n terms b × b × ... × b |
|
||
337 |
Extract the integer value i from its string representation s, in radix b
|
|||
338 |
Create a new bidirectional map bm and insert the pair (42, "forty-two")
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|
||
339 |
Set all the elements of the byte array a to zero
|
|
||
340 |
Assign to c the value of the last character of the string s.
Explain the type of c, and what happens if s is empty. Make sure to properly handle multi-bytes characters. |
|||
341 |
Set i to the position of the last occurrence of the string y inside the string x, if exists.
Specify if i should be regarded as a character index or as a byte index. Explain the behavior when y is not contained in x. |
|||
342 |
Determine if the current year is a leap year.
|
|
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|
343 |
Rename the file at path1 into path2
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|
||
344 |
Assign to ext the fragment of the string f after the last dot character, or the empty string if f does not contain a dot.
E.g. "photo.jpg" -> "jpg" ext must not contain the dot character. |
|
||
345 |
Create the integer value i initialized from its string representation s (in radix 10)
Use an integer type that can hold huge values. Explain what happens if s cannot be parsed. |
|
||
346 |
Create the list y from the list x repeated n times
|
|||
347 |
Copy the directory path1 to path2, with all its contents
|
|
||
348 |
Parse a number, a, into a mathematical fraction, f.
For example, 0.5 is `1/2`, and 3.125 is `3 1/8`. https://en.wikipedia.org/wiki/Fraction |
|
||
349 |
Parse a value, f, into a decimal number, a.
For example, `1/2` is 0.5, and `3 1/8` is 3.125. https://en.wikipedia.org/wiki/Fraction |
|
||
350 |
Generate a collection of "enumerated" values.
For example, Python's `enumerate` built-in function. https://docs.python.org/3/library/functions.html#enumerate |
|
||
351 |
Generate a "zipped" list z of pairs of elements from the lists a, b having the same length n.
The result z will contain n pairs. |
|
||
353 |
Set the boolean b to true if the list items has all its elements in increasing order, false otherwise.
The order is not strict: the ordered list may contain duplicate elements. |
|
||
354 |
Set the value for the key k in the map m to 1 if the entry doesn't exist yet in m, or increment the entry value if it already exists.
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|
||
355 |
Assign to y the absolute value of the number n
|
|
||
356 |
Create the list of integers items for the string s containing integers separated by one or more whitespace characters (space, tab, newline).
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|
||
357 |
Swap the elements at indices i, j in the list items
|
|
||
358 |
Create the end-user text, s, specifying the quantity, a, of unit x.
For example, "0 files", "1 file", or "1,000 files". |
|
||
360 |
Create the end-user text, s, specifying the contents of list a.
For example, — 'A', 'A and B', 'A, B, and C' |
Alternative implementation:
|