#include <bits/stdc++.h>
using namespace std;

int main() {
	int n; cin >> n;
	vector<int> arr(n);
	int tot_sum = 0;
	for(int i = 0; i < n; i++){
		int temp;
		cin >> temp;
		tot_sum += temp;
		arr[i] = temp;
	}
	if(tot_sum % 4 != 0)
	return 0;
	
	int y = tot_sum/4;
	int county = 0;
	int count2y = 0;
	int ans = 0;
	
	int pre_sum = 0;
	for(int i = 0; i < n-1; i++){
		pre_sum += arr[i];
		if(pre_sum == 3*y)
			ans += count2y;
		if(pre_sum == 2*y)
			count2y += county;
		if(pre_sum == y)
			county++;
	}
	cout << ans;
	return 0;
}