Envío 1280

Código

#include <iostream>
#include <vector>

using namespace std;

int main() {
   int n, sum = 0;
   cin >> n;
   vector<int> a(n);
   for (int i = 0; i < n; i++)
   {
      cin >> a[i];
      sum += a[i];
   }
   int left = a[0];
   int right = 0;
   for (int i = 1; i < n; i++)
   {
      right = sum - left;
      if (left > 0 and right <0){
         cout << i;
         return 0;
      }
      left += a[i];
   }
   cout << "Impossible";
   return 0;
}