Permutations in JavaScript?

Question

I\'m trying to write a function that does the following:

• takes an array of integers as an argument (e.g. [1,2,3,4])
• creates an array of all the possib

Answer 1

#!/usr/bin/env node
"use strict";

function perm(arr) {
    if(arr.length<2) return [arr];
    var res = [];
    arr.forEach(function(x, i) {
        perm(arr.slice(0,i).concat(arr.slice(i+1))).forEach(function(a) {
            res.push([x].concat(a));
        });
    });
    return res;
}

console.log(perm([1,2,3,4]));