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