JAVASCRIPT

sort array without changing original array

let sorted  = [].concat(arr).sort(function(a, b) {
    return a - b;
  })

sort array without changing the original js

// You need to copy the array before you sort it.
// One way with es6:
const sorted = [...arr].sort();

// or use slice() without arguments
const sorted = arr.slice().sort();

Return a Sorted Array Without Changing the Original Array

function (arr) {
  return [].concat(arr).sort(function(a, b) {
    return a - b;
  });
}