#include <bits/stdc++.h>   long long n, i, k, j, t, b;   char a[2500];   bool s;   using namespace std;   int main() {     k = 0;     cin >> n;     for (i = 1; i <= n; i++) {       cin >> a[i];       if (a[i] ==  H ) k++;     }     b = n - k;     for (i = n + 1; i <= 2 * n; i++) a[i] = a[i - n];     for (i = 1; i <= 2 * n; i++)       if (i + k <= 2 * n) {         t = 0;         for (j = i; j < i + k; j++)           if (a[j] !=  H ) t++;         if (t < b) b = t;       }     cout << b << endl;     return 0;   }   