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Scheme  

1 
Print a literal string on standard output


2 
Loop to execute some code a constant number of times



3 
Like a function which doesn't return any value, thus has only side effects (e.g. Print to standard output)

Alternative implementation:


4 
Create a function which returns the square of an integer



5 
Declare a container type for two floatingpoint numbers x and y


6 
Do something with each item x of an arraylike collection items, regardless indexes.

(define (doSomething x) (if (not (null? x)) (begin (display "Item=") (display (car x)) (newline) (doSomething (cdr x))))) Alternative implementation:
(define (sum a b) (sumiter a b 0)) (define (sumiter index n sum) (if (= n index) (+ sum index) (+ (sumiter n (+ index 1) (+ sum index))) ) 

7 
Print each index i with its value x from an arraylike collection items


8 
Create a new map object x, and provide some (key, value) pairs as initial content.



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.


10 
Generate a random permutation of the elements of list x


11 
The list x must be nonempty.


12 
Check if the list contains the value x.
list is an iterable finite container. 
(define (contains list x) (cond [(null? list) #f] [(equal? (car list) x) #t] [else (contains (cdr list) x)])) 

14 
Pick a random number greater than or equals to a, strictly inferior to b. Precondition : a < b.


15 
Pick a random integer greater than or equals to a, inferior or equals to b. Precondition : a < b.


16 
Call a function f on every node of binary tree bt, in depthfirst infix order


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.


19 
Reverse the order of the elements of list x.
This may reverse "inplace" and destroy the original ordering. 

21 
Swap the values of the variables a and b


22 
Extract the integer value i from its string representation s (in radix 10)


26 
Declare and initialize a matrix x having m rows and n columns, containing real numbers.


28 
Sort the elements of the list (or arraylike collection) items in ascending order of x.p, where p is a field of the type Item of the objects in items.

(definestruct item (p x y) #:transparent) (define items (list (item 1 2 3) (item 0 0 0) (item 5 2 1))) (sort items < #:key itemp) 

29 
Remove ith 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. 

31 
Create the recursive function f which returns the factorial of the nonnegative integer i, calculated from f(i1)


35 
Implement a function compose (A > C) with parameters f (A > B) and g (B > C), which returns composition function gâ€‰âˆ˜â€‰f


36 
Implement a function compose which returns composition function gâ€‰âˆ˜â€‰f for any functions f and g having exactly 1 parameter.


37 
Transform a function that takes multiple arguments into a function for which some of the arguments are preset.


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. 

41 
Create string t containing the same characters as string s, in reverse order.
Original string s must remain unaltered. Each character must be handled correctly regardless its number of bytes in memory. 

45 
Sleep for 5 seconds in current thread, before proceeding with the next instructions.



48 
Assign to variable s a string literal consisting in several lines of text, including newlines.

(define s #<<EOF This is my multline literal Line number two! This line starts with two spaces EOF ) ;; Can't put ) on the same line as EOF. 

49 
Build list chunks consisting in substrings of input string s, separated by one or more space characters.


50 
Write a loop that has no end clause.


51 
Determine whether the map m contains an entry for the key k


53 
Concatenate elements of string list x joined by the separator ", " to create a single string y.


54 
Calculate the sum s of the integer list or array x.


55 
Create the string representation s (in radix 10) of the integer value i.


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 inplace.


64 
Assign to x the value 3^247



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. 

76 
Create the string s of integer x written in base 2.
E.g. 13 > "1101" 

77 
Declare a complex x and initialize it with value (3i  2). Then multiply it by i.



81 
Declare integer y and initialize it with the rounded value of floating point number x .
Ties (when the fractional part of x is exactly .5) must be rounded up (to positive infinity). 


87 
Exit immediately.
If some extra cleanup work is executed by the program runtime (not by the OS itself), describe it. 


93 
Implement procedure control which receives one parameter f, and runs f.


110 
Set the boolean blank to true if the string s is empty, or null, or contains only whitespace ; false otherwise.


117 
Set n to the number of elements of the list x.


119 
Remove duplicates from the list x.
Explain if the original order is preserved. 

126 
Write a function foo that returns a string and a boolean value.


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. 

134 
Declare and initialize a new list items, containing 3 elements a, b, c.


141 
Iterate in sequence over the elements of the list items1 then items2. For each iteration print the element.


143 
Iterate alternatively over the elements of the list items1 and items2. For each iteration, print the element.
Explain what happens if items1 and items2 have different size. 

163 
Print all the list elements, two by two, assuming list length is even.


165 
Assign to variable x the last element of list items.


166 
Create the list ab containing all the elements of the list a, followed by all the elements of the list b.


171 
Append element x to the list s.


182 
Output the source of the program.


191 
Given a onedimensional array a, check if any value is larger than x, and execute the procedure f if that is the case


234 
Assign to string s the standard base64 encoding of the byte array data, as specified by RFC 4648.


243 
Print the contents of the list or array a on the standard output.


256 
Print the numbers 5, 4, ..., 0 (included), one line per number.


257 
Print each index i and value x from the list items, from the last down to the first.


261 
Assign to string x the value of fields (hours, minutes, seconds) of date d, in format HH:MM:SS.



265 
Set the integer variable i to 42 and calculate its parity (i.e. 0 if it contains an even number of bits, 1 if it contains an odd number of bits).


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. 