#include <bits/stdc++.h>


using namespace std;
ifstream f("inversmodular.in");
ofstream g("inversmodular.out");
long long x,y,a,n;
void gcd(long long &x,long long &y,int a,int b)
{
    if(b==0)
    {
        x=1;
        y=0;
    }
    else
    {
        gcd(x,y,b,a%b);
        long long aux=x;
        x=y;
        y=aux-y*(a/b);
    }
}
int main()
{
    f>>a>>n;
    gcd(x,y,a,n);
    if(x<=0)
        x=n+x%n;
    g<<x;
    return 0;
}