freeCodeCamp/curriculum/challenges/english/10-coding-interview-prep/project-euler/problem-52-permuted-multiples.md

id	title	challengeType	forumTopicId	dashedName
5900f3a01000cf542c50feb3	Problem 52: Permuted multiples	5	302163	problem-52-permuted-multiples

--description--

It can be seen that the number, 125874, and its double, 251748, contain exactly the same digits, but in a different order.

Find the smallest positive integer, x, such that 2x, 3x, 4x, 5x, and 6x, contain the same digits.

--hints--

permutedMultiples() should return a number.

assert(typeof permutedMultiples() === 'number');

permutedMultiples() should return 142857.

assert.strictEqual(permutedMultiples(), 142857);

--seed--

--seed-contents--

function permutedMultiples() {

  return true;
}

permutedMultiples();

--solutions--

function permutedMultiples() {
    const isPermutation = (a, b) =>
        a.length !== b.length
            ? false
            : a.split('').sort().join() === b.split('').sort().join();


    let start = 1;
    let found = false;
    let result = 0;

    while (!found) {
        start *= 10;
        for (let i = start; i < start * 10 / 6; i++) {
            found = true;
            for (let j = 2; j <= 6; j++) {
                if (!isPermutation(i + '', j * i + '')) {
                    found = false;
                    break;
                }
            }
            if (found) {
                result = i;
                break;
            }
        }
    }

    return result;
}