#include <bits/stdc++.h>
using namespace std;
#include <atcoder/string>
using namespace atcoder;
using ll = long long;
using P = pair<ll,ll>;
#define fix(x) fixed << setprecision(x)
#define asc(x) x, vector<x>, greater<x>
#define rep(i, n) for(ll i = 0; i < n; i++)
#define all(x) (x).begin(),(x).end()
template<class T>bool chmin(T&a, const T&b){if(a>b){a=b;return 1;}return 0;}
template<class T>bool chmax(T&a, const T&b){if(a<b){a=b;return 1;}return 0;}
constexpr ll INFLL = (1LL << 62), MOD = 998244353;
constexpr int INF = (1 << 30);

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int t;
    cin >> t;
    while(t--){
        int cnt = 0, n;
        string s;
        cin >> n >> s;
        auto x = z_algorithm(s);
        for(int i=1;i<n;i++){
            if(x[i]<i) cnt += (s[x[i]] < s[i+x[i]]);
            else if(i<n-i) cnt++;
        }
        cout << cnt << '\n';
    }
    return 0;
}