#include<iostream>
#include<exception>
using namespace std;

class fulle:public exception{
    const char* what() const noexcept{return "Error: Insufficient Slots")
};
int main(){
    int slots,students;
    if(!(cin>>slots>>students) || slots<0 || students<0){
        cout<<"Invalid Input";
        return 0;
        
    }
    try{
        if(students>slots)throw fulle();
        cout<<"Enrollment successful";
        
    }catch (fulle& e){
        cout<<e.what();
    }
    return 0;
    
}