Envío 1333

Código

#include <iostream>
#include <vector>
using namespace std;

int main(void)
{
    long size, lp = 0, rp = 0;
    cin >> size;

    vector<int> toRight(size);
    vector<int> toLeft(size);

    for (long i = 0; i < size; i++)
    {
        cin >> toRight[i];
        toLeft[i] = toRight[i];
    }

    for (long i = size - 2; i >= 0; i--)
        toLeft[i] += toLeft[i + 1];

    for (long i = 1; i < size; i++)
        toRight[i] += toRight[i - 1];

    for (long i = 0; i < size - 1; i++)
    {
        if (toRight[i] > 0 && toLeft[i + 1] < 0)
        {
            cout << i + 1 << endl;
            return (0);
        }
    }

    cout << "Impossible" << endl;
    return (0);
}