Array full arrangement output algorithm implemented by JS_javascript skills

The example in this article describes the full array output algorithm implemented by JS. Share it with everyone for your reference. The specific analysis is as follows:

This js code fully arranges and outputs the array, improving some old codes
Randomly selecting m (m ≤ n) elements from n different elements and arranging them in a certain order is called an arrangement of m elements from n different elements. When m=n, all permutations are called full permutations.

function permute(input) {
  var permArr = [],
  usedChars = [];
  function main(input){
    var i, ch;
    for (i = 0; i < input.length; i++) {
      ch = input.splice(i, 1)[0];
      usedChars.push(ch);
      if (input.length == 0) {
        permArr.push(usedChars.slice());
      }
      main(input);
      input.splice(i, 0, ch);
      usedChars.pop();
    }
    return permArr
  }
  return main(input);
};
console.log(permute([5, 3, 7, 1]));

I hope this article will be helpful to everyone’s JavaScript programming design.