Be concise.
Be useful.
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Please try to avoid dependencies to third-party libraries and frameworks.
const s = ((n) => {
const alphanum = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
let s = "";
for (let i = 0; i < n; i += 1) {
s += alphanum[~~(Math.random() * alphanum.length)];
}
return s;
})(n);~~ is a faster way to call Math.floor().
Note that Math.random is not cryptographically secure.
Note that Math.random is not cryptographically secure.
const alphanum = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
func randomString(n int) string {
a := make([]byte, n)
for i := range a {
a[i] = alphanum[rand.Intn(len(alphanum))]
}
return string(a)
}Each of these runes fits in a single byte.
The default RNG can be run concurrently, as it incurs the cost of a Mutex.
Note that the package math/rand is not crypto-secure
The default RNG can be run concurrently, as it incurs the cost of a Mutex.
Note that the package math/rand is not crypto-secure
const alphanum = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
func randomString(n int, rng *rand.Rand) string {
a := make([]byte, n)
for i := range a {
a[i] = alphanum[rng.Intn(len(alphanum))]
}
return string(a)
}Using a custom rand.Rand instance lets you control the seed, and is also better for performance (lock-free).
Note that the package math/rand is not crypto-secure.
Note that the package math/rand is not crypto-secure.
var alphanum = []rune("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789")
func randomString(n int, rng *rand.Rand) string {
a := make([]rune, n)
for i := range a {
a[i] = alphanum[rng.Intn(len(alphanum))]
}
return string(a)
}This version is slightly more generic: it works with an alphabet of arbitrary runes, which don't need to fit in a single byte each.
Note that the package math/rand is not crypto-secure.
Note that the package math/rand is not crypto-secure.
String s = "";
Integer z[], i = 0;
char a[] = new char[62], c;
for (c = 'a'; c <= 'z'; ++c) a[i++] = c;
for (c = 'A'; c <= 'Z'; ++c) a[i++] = c;
for (c = '0'; c <= '9'; ++c) a[i++] = c;
z = new Integer[62];
for (i = 0; i < 62; ++i) z[i] = i;
shuffle(asList(z));
for (i = 0; i < n; ++i) s = s + a[z[i]];function RandomString(Size: Integer): String;
const
Chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
Len = Length(Chars);
var
i: Integer;
begin
Result := '';
SetLength(Result, Size);
for i := 1 to Size do
begin
Result[i] := Chars[Random(Len)+1];
end;
end; Pascal strings start at index 1.
Then const Len will be calculated at compile time.
Random(Len) returns a random number larger or equal to 0 and strictly less than Len.
Then const Len will be calculated at compile time.
Random(Len) returns a random number larger or equal to 0 and strictly less than Len.
my @chars = ('A'..'Z', 'a'..'z', '0'..'9');
my $s='';
$s .= $chars[int rand @chars] for 1..$n;Defines a list of the desired characters. Initializes $s to an empty string. Uses int of rand (length of the character list in scalar context) to get a random index. Accesses the random character and appends it to $s (.= is string append). Repeats this $n times.
a = list(ascii_letters + digits)
shuffle(a)
s = ''.join(a[:n])