hbarudin

/*
Write some code, that will flatten an array of arbitrarily nested arrays of
integers into a flat array of integers. e.g. [[1,2,[3]],4] -> [1,2,3,4].
*/

var array_flatten = function (arr, flattened_arr = []) {
  if(!Array.isArray(arr)) {
    // Fow now, arbitrarily decide to just break out if input is invalid. Could handle other ways (return an empty array, for example), but this is OK for now. 
    console.error('Invalid input.');
    return;