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

// SAYED AL MAMUN_LU

int main()
{
    int t;
    cin >> t;
    while (t--)
    {
        int n;
        cin >> n;
        char samp[n];
        for (int h = 0; h < n; h++)
        {
            cin >> samp[h];
        }

        unordered_map<char, int> freq;
        for (int i = 0; i < n; i++)
        {
            freq[samp[i]]++;
        }

        int sum = 0;
        for (auto &[key, value] : freq)
        {
            sum += (value * (value - 1)) / 2;
        }

        cout << 2*sum << endl;
    }
    return 0;
}