#include <bits/stdc++.h>
#include <x86intrin.h>
using namespace std;
using namespace numbers;

// z[i]: largest prefix(suffix if Reverse) starting(ending if Reverse) at i that is also a proper prefix(suffix if Reverse)
// O(n)
template<class Char_Type, bool Reverse = false>
vector<int> z_function(vector<Char_Type> s){
	if(Reverse) reverse(s.begin(), s.end());
	int n = (int)s.size();
	vector<int> z(n);
	for(auto i = 1, j = 0; i < n; ++ i){
		if(i < j + z[j]) z[i] = min(j + z[j] - i, z[i - j]);
		while(i + z[i] < n && s[z[i]] == s[i + z[i]]) ++ z[i];
		if(i + z[i] > j + z[j]) j = i;
	}
	if(Reverse) reverse(z.begin(), z.end());
	return z;
}

int main(){
	cin.tie(0)->sync_with_stdio(0);
	cin.exceptions(ios::badbit | ios::failbit);
	auto __solve_tc = [&](auto __tc_num)->int{
		int n;
		string s;
		cin >> n >> s;
		auto z = z_function(vector<int>(s.begin(), s.end()));
		int res = 0;
		for(auto i = 1; i < n; ++ i){
			int len = min(z[i], i);
			res += n - i != len && (i == len || s[len] < s[i + len]);
		}
		cout << res << "\n";
		return 0;
	};
	int __tc_cnt;
	cin >> __tc_cnt;
	for(auto __tc_num = 0; __tc_num < __tc_cnt; ++ __tc_num){
		__solve_tc(__tc_num);
	}
	return 0;
}

/*

*/

////////////////////////////////////////////////////////////////////////////////////////
//                                                                                    //
//                                   Coded by Aeren                                   //
//                                                                                    //
////////////////////////////////////////////////////////////////////////////////////////