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