til/javascript/generate-random-integers.md

Generate Random Integers

JavaScript's Math module has a built-in random function.

> Math.random();
0.4663311937101857

It can be used to generate random floats between 0 and 1.

If you want integers, though, you're going to have to build your own function.

function getRandomInt(max) {
  return Math.floor(Math.random() * Math.floor(max));
}

> getRandomInt(10);
1
> getRandomInt(10);
7
> getRandomInt(10);
2

This function allows you to randomly generate numbers between 0 (inclusive) and max, a number you specify (exclusive).

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