#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
int main () {
	int T;
	cin >> T;
	while (T--) {
		int N;
		cin >> N;
		string s;
		cin >> s;
		auto v = z_algorithm(s);
		int ans = 0;
		for (int i = 1; i < N; i ++) {
			int l = v[i];
			if (l < min(i, N - i)) {
				ans += s[l] < s[i + l];
			} else {
				ans += i < (N - i);
			}
		}
		cout << ans << endl;
	}
}