#include <bits/stdc++.h>

#define endl '\n'
#define F first
#define S second
#define pb push_back

typedef long long ll;
typedef unsigned long long ull;

using namespace std;

template<typename T>
void scan(vector<T> &v) {for (T &x : v) cin >> x;}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

#ifdef LUCHADOR
    freopen("/home/joker/Documents/code/in", "r", stdin);
    freopen("/home/joker/Documents/code/out", "w", stdout);
#endif

    int t;
    cin >> t;

    while (t--) {
        int n;
        cin >> n;

        string s;
        cin >> s;

        map<char, int> pos;
        for (char &c : s) {
            pos[c]++;
        }

        ll ways = 0LL;
        for (auto &[_, c] : pos) {
            ways += 1LL * (c - 1) * c;
        }

        cout << ways << endl;
    }

    return 0;
}

// 1 3, 3 1

// 1 2 3
// 1 2
// 1 3
// 2 3

// 1 2 3 4
// 1 2
// 1 3
// 1 4
// 2 3
// 2 4
// 3 4