#include <bits/stdc++.h>

using namespace std;
using ll = long long;

template <typename T>
vector<int> z_algorithm(T &S){
    vector<int> Z(S.size());
    Z[0] = S.size();
    int i=1, j=0;
    while(i < S.size()){
        while(i+j < S.size() && S[j] == S[i+j]) j++;
        Z[i] = j;

        if (j == 0){
            i++;
            continue;
        }
        int k=1;
        while(k < j && k + Z[k] < j){
            Z[i+k] = Z[k];
            k++;
        }
        i += k;
        j -= k;
    }

    return Z;
}

void solve(){
    int N, ans=0, k;
    string S;
    cin >> N >> S;
    vector<int> z = z_algorithm(S);

    for (int i=1; i<N; i++){
        if (i < z[i]) ans++;
        else if (i == z[i] && i != N-i) ans++;
    }

    cout << ans << endl;
}

int main(){

    int T;
    cin >> T;
    while(T){
        T--;
        solve();
    }

    return 0;
}