#include<iostream>
using namespace std;
class ClassFullException{};
int main(){
    int slot,students;
    cin>>slots>>students;
    if(slots<0||students<0){
        cout<<"Invalid input";
        return 0;
    }
    try{
        if(students>slots)throw
        ClassFullException();
        cout<<"Enrollment successful";
    }
    catch(ClassFullException){
        cout<<"Error:Insufficient Slots";
    }
}