#include <bits/stdc++.h>
#define MAX 20024
using namespace std;

ifstream in("inversmodular.in");
ofstream out("inversmodular.out");

void euclid(int a, int b, int & x, int & y){
    if(!b){
        x = y = 1;
    }
    else{
        int x1, y1;
        euclid(b, a % b, x1, y1);
        x = y1;
        y = x1 - a / b * y1;
    }
}

int main(){
    int a, n, x, y;
    in>>a>>n;
    euclid(a, n, x, y);
    while(x < 0)
        x += n;
    out<<x;
}