#include <iostream>
#include <fstream>
using namespace std;

void eu(int a, int b, int d, int & x, int & y){
     if(b==0){
              x=1;
              y=0;
              d=a;
              }else
              {
              int x0, y0;
              eu(b, a%b, d, x0, y0);
              x=y0;      
              y=x0-(a/b)*y0;
              }
     
     }

int main(){
    ifstream inr ("inversmodular.in");
    ofstream our ("inversmodular.out");
    int a,m,d,x,y;
    inr >> a;
    inr >> m;
    eu(a,m,d,x,y);
    our << (x%m+m)%m;
    return 0;
    }