#include <bits/stdc++.h>
using namespace std;
string s;
int n, m;
int f[150][150][250][2];
int main() {
  cin >> s;
  n = s.size();
  scanf("%d", &m);
  f[0][m][n][1] = true;
  for (int i = 0; i < n; i++)
    for (int j = 0; j <= m; j++)
      for (int k = 0; k <= n * 2; k++)
        for (int l = 0; l < 2; l++)
          if (f[i][j][k][l])
            if (s[i] == 'T') {
              f[i + 1][j][k][1 - l] = true;
              if (j != 0 && k - 1 + 2 * l >= 0)
                f[i + 1][j - 1][k - 1 + 2 * l][l] = true;
            } else {
              if (k - 1 + 2 * l >= 0) f[i + 1][j][k - 1 + 2 * l][l] = true;
              if (j != 0) f[i + 1][j - 1][k][1 - l] = true;
            }
  int i = 0;
  for (int j = 0; j <= m; j++)
    if (j % 2 == 0)
      for (int k = 0; k <= n * 2; k++)
        for (int l = 0; l < 2; l++)
          if (f[n][j][k][l]) {
            if (k - n < 0 && n - k > i) i = n - k;
            if (k - n > 0 && k - n > i) i = k - n;
          }
  printf("%d\n", i);
  return 0;
}
