#include<iostream>
#include<iomanip>
using namespace std;
class c{
    public:
    static double sum;
    static void solve()
    {
        int n;double r;
        if(!(cin >> n)) return;
        while (n--)
        {
            if (!(cin >> r))
            {
                cout <<"Incomplete Data\n";
                return;
            }
                    if(r<0)
        {
            cout<<"Invalid Rainfall\n";
            return;
        }
        sum +=r;
    }
        cout << fixed << setprecision(2) << sum <<"\n";
    }
};
double C::sum =0;
int main()
{
    C::solve();
    return 0;
}