#include <bits/stdc++.h>
#define ll long long
using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");
int euclidExtins(int a, int b, int &x, int &y){
    if(b == 0){
        x = 1;
        y = 0;
        return a;
    }
    int x0, y0;
    int d = euclidExtins(b, a%b, x0, y0);
    x = y0;
    y = x0 - (a/b)*y0;

    return d;
}
int main(){
    int a,n, x, y;
    fin >> a >> n;
    euclidExtins(a,n,x,y);
    while(x < 0){
        x += n;
    }
    fout << x;

    return 0;
}