int rand() {
    static unsigned int seed = 1337191337;
    unsigned int buf[] = {
        (seed*31832)%677,
        (seed*32932)%2332
    };
    seed = buf[1]*223238;
    seed *= seed << 4;
    seed %= 410829;
    seed = buf[0] * 1892823 % 23891;
    seed = buf[0];
    return seed;
}