#include <bits/stdc++.h>

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