#include<iostream>
#include<fstream>
using namespace std;
 
inline void gcd(int a, int b, int &x, int &y)
{
    if(b==0) {
        x=1;
        y=0;
    }
    else {
        int x0,y0;
        gcd(b,a%b,x0,y0);
        x=y0;
        y=x0-(a/b)*y0;
    }
}
 
int main ()
{
    int a,n,x,y;
    ifstream f("inversmodular.in");
    ofstream g("inversmodular.out");
    f>>a>>n;
    f.close();
    gcd(a,n,x,y);
    while(x<=0)
        x=x+n;
    if(x==n)
        x=0;
    g<<x;
    g.close();
    return 0;
}