How to be sure that the next randomly selected value from an array is not the same as the current one using Javascript?

Question

I am randomly selecting values from an array. I want to be sure that the next selected value is not the same as the current one. How can I implement this rule in Javascript?

const pages = [1, 2, 3, 4, 5];
const random = Math.floor(Math.random() * pages.length);
console.log(pages[random]);

What is the "current" one? How is this code called/used? – evolutionxbox Dec 23 '21 at 02:13 — evolutionxbox, Dec 23 '21 at 02:13

score 1 · Answer 1 · answered Dec 23 '21 at 02:17

1

You could filter pages removing current value and only after that select random element.

answered Dec 23 '21 at 02:17

yjay

942
4
11

score 1 · Answer 2 · answered Dec 23 '21 at 02:18

If the one you pick is the same as the previous one, pick a new one:

const pages = [1, 2, 3, 4, 5];
const random = Math.floor(Math.random() * pages.length);
console.log(pages[random]);

let random2;
// Pick a new one:
while (random == ( random2 = Math.floor(Math.random() * pages.length)));

This assumes every value in the array is different, so it just cares that the two indexes (random and random2) are different.

How to be sure that the next randomly selected value from an array is not the same as the current one using Javascript?

2 Answers2