#include "df.h"

uint64 expm(uint64 m, uint64 e, uint64 mod)
{
    uint128 _r = 1;
    uint128 _m = (uint128)m;
    uint128 _mod = (uint128)mod;

    while (e > 0) {
        if (e % 2 == 1) {
            _r = (_r * _m) % _mod;
        }
        _m = (_m * _m) % _mod;
        e = e / 2;
    }

    return (uint64)_r;
}

uint64 generateur(uint64 p)
{
    uint64 q = (p - 1) / 2;
    uint64 g = 2;
    
    while (1) {
        if (expm(g, 2, p) != 1 && expm(g, q, p) != 1) {
            return g;
        }
        g++;
    }
}