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

ifstream f("inversmodular.in");
ofstream g("inversmodular.out");

void cmmdc(int &x,int &y,int a,int b)
{
    if(!b)
    {
        x=1;y=0;
    }
    else
    {
        cmmdc(x,y,b,a%b);
        int aux=x;
        x=y;
        y=aux- y*(a/b);
    }
}

int main()
{

    int x,y,a,b;
    f>>a>>b;
    cmmdc(x,y,a,b);
    if(x<0)
        x=b+x%b;
    g<<x;
    f.close();
    g.close();
    return 0;
}