Sandbox::https://github.com/sibalonecoding-code/JavaScript/blob/master/Backtracking/GeneratePermutations.js

Repository navigation

36 lines (31 loc) · 851 Bytes

* Problem Statement: Generate all distinct permutations of an array (all permutations should be in sorted order);

* What is permutations?

* - Permutation means possible arrangements in a set (here it is an array);

* Reference to know more about permutations:

* - https://www.britannica.com/science/permutation

const swap = (arr, i, j) => {

const newArray = [...arr]

;[newArray[i], newArray[j]] = [newArray[j], newArray[i]] // Swapping elements ES6 way

return newArray

}

const permutations = (arr) => {

const P = []

const permute = (arr, low, high) => {

if (low === high) {

P.push([...arr])

return P

}

for (let i = low; i <= high; i++) {

arr = swap(arr, low, i)

permute(arr, low + 1, high)

}

return P

}

return permute(arr, 0, arr.length - 1)

}

export { permutations }