B

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

int main() {
    int t;
    cin>>t;
    while(t--)
    {
        int n;
        string s;
        cin >> n >> s;

        int val = 0;
        map<int, int> sum;
        sum[0]++;

        long long int ans = n *1ll* (n + 1) / 2;

        for (auto e : s){
            if (e == '1')
                val++;
            else
                val--;

            sum[val]++;
            ans += sum[val];
        }

        cout << ans << "\n";
    }
}