freeCodeCamp/curriculum/challenges/english/08-coding-interview-prep/project-euler/problem-52-permuted-multipl...

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---
id: 5900f3a01000cf542c50feb3
challengeType: 5
title: 'Problem 52: Permuted multiples'
---
## Description
<section id='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.
</section>
## Instructions
<section id='instructions'>
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: <code>permutedMultiples()</code> should return 142857.
testString: assert.strictEqual(permutedMultiples(), 142857);
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
function permutedMultiples() {
// Good luck!
return true;
}
permutedMultiples();
```
</div>
</section>
## Solution
<section id='solution'>
```js
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;
}
```
</section>