#include <bits/stdc++.h>

using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");
int a,n,invers,it;
void euclid(int a, int b, int &x, int &y)
{
    if(!b)
        x=1,y=0;
    else
    {
        int x0,y0;
        euclid(b,a%b,x0,y0);
        x=y0;
        y=x0-y0*(a/b);
    }
}
int main()
{
    fin>>a>>n;
    euclid(a,n,invers,it);
    if(invers<=0)
        invers=n+invers%n;
    fout<<invers<<"\n";
    return 0;
}