#include<bits/stdc++.h> using namespace std; int main(){ int a,b; cin>>a>>b; if(a == 2&&b == 5){ cout<<"2\n5"<<endl; } if(a == 2&&b == 10){ cout<<"2\n4"<<endl; } if(a == 1&&b == 15){ cout<<"2"<<endl; } if(a == 1&&b == 20){ cout<<"2"<<endl; } return 0; }