input: def add_large_numbers(num1, num2):
      """ This function adds two large numbers represented as strings. It reads the strings
      from right to left and uses carry to handle the addition.
      >>> add_large_numbers("111", "1337")
      '1448'
      >>> add_large_numbers("999", "999")
      '1998'
      >>> add_large_numbers("123", "456")
      '579'
      """
output:     carry = 0
      result = []
      len1, len2 = len(num1), len(num2)
      max_len = max(len1, len2)
      
      for i in range(max_len):
          digit1 = int(num1[len1 - 1 - i]) if i < len1 else 0
          digit2 = int(num2[len2 - 1 - i]) if i < len2 else 0
          total = digit1 + digit2 + carry
          carry = total // 10
          result.append(str(total % 10))
      
      if carry:
          result.append(str(carry))
      
      return ''.join(result[::-1])