#include <stddef.h>

static unsigned int seed = 0;

void srand(unsigned int _seed)
{
    seed = _seed;
}

int rand(void)
{
    int next = seed;
    int result;

    next *= 1103515245;
    next += 12345;
    result = (int)(next / 65536) % 2048;

    next *= 1103515245;
    next += 12345;
    result <<= 10;
    result ^= (int)(next / 65536) % 1024;

    next *= 1103515245;
    next += 12345;
    result <<= 10;
    result ^= (int)(next / 65536) % 1024;

    seed = next;
    return result;
}