#include <iostream>
#include <fstream>
#define ll long long

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