Implementation
C++

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Other implementations
x.get((int)(Math.random()*x.size()))
x[Math.floor(Math.random() * x.length)]
import random
random.choice(x)
import "math/rand"
x[rand.Intn(len(x))]
#include <stdlib.h>
x[rand() % x_length];
$x[ array_rand($x) ]
my @x = ('a', 'list', 'of', 'random', 'items');
print $x[rand @x];
import std.random;
x.randomSample(1);
x[new Random().nextInt(x.length)];
element := x[random(length(x))];
uses classes;
element := x.Items[random(x.count)];
import System.Random (randomR)
(\l g -> l !! (randomR (0, length l) g))
Enum.random(x)
https://github.com/inaka/erlang-katana
ktn_random:pick(X)
lists:nth(rand:uniform(length(X)), X).
x[math.random(#x)]
x.sample
import scala.util.Random
val x = List(1, 2, 3, 4)
x.apply(Random.nextInt(x.size))
using System;
using System.Collections.Generic;
x[new Random().Next(x.Count)];
import "math/rand"
func pickT(x []T) T {
	return x[rand.Intn(len(x))]
}
use rand::{self, Rng};
x[rand::thread_rng().gen_range(0, x.len())]
(rand-nth x)
import System.Random (randomRIO)
(l !!) <$> randomRIO (0, length l - 1)
extern crate rand;
use rand::{thread_rng, Rng};
let choice = thread_rng().choose(&x).unwrap();
import java.util.concurrent.ThreadLocalRandom;
x.get(ThreadLocalRandom.current().nextInt(0, x.size()))
(nth (random (length x)) x)
(nth (random (length x)) x)
list.random()
call random_number (a)
x(lbound(x) + int(a*ubound(x))
const x = [1, 'two', 3, 4, 'five', 'six', 7, 8, 'nine' ];

const randomElement = x[~~(Math.random() * x.length)];