#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
#define rep(i, n) for(int i=0;i<(n);++i)
#define rep1(i, n) for(int i=1;i<=(n);i++)
#define ll long long
using mint = modint998244353;
using P = pair<ll,ll>;
using lb = long double;
using T = tuple<ll, ll, ll>;
#ifdef LOCAL
#  include <debug_print.hpp>
#  define dbg(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#  define dbg(...) (static_cast<void>(0))
#endif

int main()
{
    int t;
    cin >> t;
    rep(_,t){
        int n;
        string s;
        cin >> n >> s;
        int ans = 0;
        vector<int> z = z_algorithm(s);
        dbg(z);
        for(int i=1;i<n;i++){
            int now = z[i];
            if(now>=i) {
                if(i<n/2+1) ans++;
            }
            else if(s[now]<s[i+now]) ans++;
        }
        cout << ans << endl;
    }

    return 0;
}