#include <iostream>
using namespace std;

int main() {
    int n;
    cin >> n;
    int a[n];
    for(int i = 0; i < n; i++) {
        cin >> a[i];
    }
    int L = 0;
    int R = n - 1;
    int number_of_merges = 0;
    while(L <= R) {
        if(a[L] == a[R]) {
            L++;
            R--;
        }
        else if(a[L] < a[R]) {
            L++;
            a[L] += a[L - 1];
            number_of_merges++;
        }
        else {
            R--;
            a[R] += a[R + 1];
            number_of_merges++;
        }
    }
    cout << number_of_merges << endl;
    return 0;
}