text: /**
   * @param {string} num1
   * @param {string} num2
   * @return {string}
   */
  var addStrings = function(num1, num2) {
  	if (num2.length > num1.length) {
  		var tmp = num1;
  		num1 = num2;
  		num2 = tmp;
  	}
  
  	var mult = 1;
  	var result = [];
  	num1 = num1.split('').reverse();
  	num2 = num2.split('').reverse();
  
  	for (var i = 0, l = Math.max(num1.length, num2.length) + 1; i < l; i++) {
  		if (i < num1.length) {
  			num1[i] = parseInt(num1[i]);
  		}
  
  		if (i < num2.length) {
  			num2[i] = parseInt(num2[i]);
  		}
  
  		result.push(0);
  	}
  
  	var carry = 0;
  	for (var i = 0, l = result.length; i < l; i++) {
  		var r = (i < num1.length) ? num1[i] : 0;
  		r += (i < num2.length) ? num2[i] : 0;
  		r += carry;
  
  		carry = Math.floor(r / 10);
  		result[i] = r % 10;
  	}
  
  	//remove leading 0
  	result = result.reverse();
  	var i = 0;
  	while (i < result.length && result[i++] === 0);
  
  	i -= 1;
  
  	if (i > 0) {
  		result = result.slice(i);
  	}
  
  	return result.join('');
  };
  
  module.exports = addStrings;
  