Roxettes!!!

#include <iostream>

uint8_t readOneByte()
{
    uint8_t ch;
    std::cin >> ch;
    if(ch >= '0' && ch <= '9')
        ch = ch - 48;
    else if (ch >= 'A' && ch <= 'F')
        ch = ch - 55;
    else if (ch >= 'a' && ch <= 'f')
        ch = ch - 87;
    else if (ch == '.')
        ch = 255;

    return (int)ch;
}

int main()
{
    std::cin.sync_with_stdio(false);
    std::cout.sync_with_stdio(false);

    uint32_t i = 4294967295;
    uint32_t result = 0;

    while (true){
        uint8_t input = readOneByte();
        if (input==255) break;
        result ^= input<<(--i%5)*4;
    }

    std::cout << std::hex << result;
    return 0;
}