#include <fstream>
std::ifstream fin("inversmodular.in");
std::ofstream fout("inversmodular.out");
inline void euclid(long long int a, long long int b, long long int &x, long long int &y) {
    if (b == 0)
        x = y = 1;
    else {
        long long int x1, y1;
        euclid(b, a % b, x1, y1);
        x = y1;
        y = x1 - a / b * y1;
    }
}
int main() {
    long long int a, MOD, x, y;
    fin >> a >> MOD;
    euclid(a, MOD, x, y);
    while (x < 0)
        x += MOD;
    fout << x;
    return 0;
}