#include <algorithm>
#include <cassert>
#include <cstdio>
#include <cstring>
#include <iomanip>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <ranges>
#include <set>
#include <string>
#include <vector>

using namespace std;

int solve() {
    int n;
    string s;
    cin >> n >> s;
    int res = 0;

    int d = n / 10;
    for (int i = 0; i < 10; i++) {
        bool ok = true;
        for (int j = 0; j < d; j++) {
            ok &= s[i * d + j] == 'T';
        }
        res += ok;
    }
    return res;
}

int main() {
    ios::sync_with_stdio(false);
    cin.exceptions(cin.failbit);
    cin.tie(0);
    cout << solve() << "\n";
}