#include <iostream>
using namespace std;
int main(){
    int n;
    cin>>n;
    try{
        if(n<1||n>12){
            throw "Invalid input";
        }
        int deposit, saving=0;
        for (int i=0;i<n;i++){
            cin>>deposit;
        if (deposit<0){
            throw "invalid input";
        }
        saving+=deposit
    }
        cout<<saving;
    }
    catch (const char*a){
        cout<<a;
    }
    return 0;
}