#include <iostream>
#include <fstream>
using namespace std;
ifstream in("inversmodular.in");
ofstream out("inversmodular.out");
int cmmdc(int a, int b, int &x, int &y)
{
    if(b==0)
    {
        x=1;
        y=0;
        return a;
    }

    int d=cmmdc(b,a%b,x,y);
    int aux=x;
    x=y;
    y=aux-y*(a/b);
    return d;
}
int main()
{
    int a,mod,x,y;
    in>>a>>mod;
    cmmdc(a,mod,x,y);
    while(x<0)
        x=x+mod;
    out<<x;
    return 0;
}