#include <bits/stdc++.h>
using namespace std;
ifstream f("inversmodular.in");
ofstream g("inversmodular.out");
int a,n;
long long inv,ins;
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(inv,ins,a,n);
    if(inv<=0)
        inv=(n+inv)%n;
    g<<inv;
    return 0;
}