#include <bits/stdc++.h>

using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");
int gcd(int a, int b, int &x, int &y){
    if(!b){
        x = 1;
        y = 0;
        return a;
    }
    int x0,y0;
    int d = gcd(b,a % b,x0,y0);
    x = y0;
    y = x0 - (a / b) * y0;
    return d;
}
int main()
{
    //cu alg euclid extins
    int n,m,x,y,d;
    fin >> n >> m;
    d = gcd(m,n,x,y);
    while(y < 0){
        y += m;
    }
    fout << y;
    return 0;
}