#include <iostream>
#include <string>
#include <algorithm>
using namespace std;

int main() {
    int T;
    cin >> T;
    while (T--) {
        int N;
        cin >> N;
        string S;
        cin >> S;
        
        // Count initial "CCPC" occurrences
        int cnt = 0;
        for (int i = 0; i <= N - 4; ++i) {
            if (S.substr(i, 4) == "CCPC") {
                ++cnt;
            }
        }
        
        int ans = cnt;

        // Try replacing each position with 'C' or 'P'
        for (char s : {'C', 'P'}) {
            for (int i = 0; i <= N; ++i) {
                int c = cnt;
                string S0 = "", S1 = "";
                
                // Construct the modified substrings S0 and S1
                for (int j = i - 3; j < i; ++j) {
                    if (0 <= j && j < N) {
                        S0 += S[j];
                        S1 += S[j];
                    }
                }
                S1 += s; // Replace one position with s
                
                for (int j = i; j < i + 3; ++j) {
                    if (0 <= j && j < N) {
                        S0 += S[j];
                        S1 += S[j];
                    }
                }

                // Recompute number of "CCPC" in S0
                for (int j = 0; j <= (int)S0.size() - 4; ++j) {
                    if (S0.substr(j, 4) == "CCPC") {
                        --c;
                    }
                }

                // Recompute number of "CCPC" in S1
                for (int j = 0; j <= (int)S1.size() - 4; ++j) {
                    if (S1.substr(j, 4) == "CCPC") {
                        ++c;
                    }
                }
                
                ans = max(ans, c);
            }
        }
        cout << ans << endl;
    }
    return 0;
}