resolve summ without cast (]:_>)

shit_cast.js

'use strict'
const super_cast = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'];

const convert = (arr_char) => {
  let real_num = 0;
  for (let i = 0; i < arr_char.length; ++i) {
    real_num = real_num + Math.pow(10, i) * super_cast.indexOf(arr_char[i]);
  };
  return real_num;
}

const sum_str = (a, b) => {
  return (convert(a.split('')) + convert(b.split(''))).toString();
}

console.log(convert(['1', '1']));
console.log(sum_str('232','23'));