brute force on https://roadrunnerwmc.github.io/blog/2020/05/08/nsmb-rng.html

bruteforce.c

// https://roadrunnerwmc.github.io/blog/2020/05/08/nsmb-rng.html takes about 10 seconds to find
// a fixed point for the random number generator

#include <assert.h>
#include <stdio.h>
#include <stdint.h>

uint32_t rand_nsmb(uint32_t *state) {
    uint64_t value = (uint64_t)(*state) * 1664525 + 1013904223;
    return *state = value + (value >> 32);
}

int main(int argc, const char **argv) {
    uint32_t candidate = ~0; 
    do {
        uint32_t state = candidate;
        if (rand_nsmb(&state) == candidate) {
            printf("found 0x%08x\n", candidate);
            return 0;
        }
    } while (candidate--);
    return 1;
}