#include<iostream>
#include<cmath>
#include<fstream>

using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");

using namespace std;
int cmmdc(int a, int b)
{
    if(b==0)return a;
    return cmmdc(b, a%b);
}

int inversModular(int a,int n){

    for(int i=1;i<1700;i++){
        if(cmmdc(n*i+1,a)>1){return (n*i+1)/a;}

    }

}
main(){
int a,n;
fin>>a>>n;
fout<<inversModular(a,n);
}