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

ifstream in("euclid3.in");
ofstream out("euclid3.out");
int cmmdc(int a, int b, int &x, int &y)
{
    if(b==0)
    {
        x=1; y=0;
        return a;
    }
    int ans = cmmdc(b, a%b, x, y);
    int aux = x;
    x = y;
    y = aux - y*(a/b);
    return ans;
}
int main()
{
    int a,mod,x,y;
    cin>>a>>mod;
    cmmdc(a,mod,x,y);
    while(x<0)
        x=x+mod;
    cout<<x;
    return 0;
}