def hex_to_dec(hex_num): hex_to_dec_map = { '0': 0, '1': 1, '2': 2, '3': 3, '4': 4, '5': 5, '6': 6, '7': 7, '8': 8, '9': 9, 'a': 10, 'b': 11, 'c': 12, 'd': 13, 'e': 14, 'f': 15 } decimal_num = 0 for i, char in enumerate(hex_num[::-1]): decimal_num += hex_to_dec_map[char] * (16 ** i) return decimal_num a=input() print(hex_to_dec(a))