#include <bits/stdc++.h>
using namespace std;
long long mod = 1000000007;
long long mod2 = 998244353;
long long mod3 = 1000003;
long long mod4 = 998244853;
long long inf = 1000000000000000000;
double pi = 2 * acos(0);
int dh[4] = {1, -1, 0, 0};
int dw[4] = {0, 0, 1, -1};
int ddh[8] = {-1, -1, -1, 0, 0, 1, 1, 1};
int ddw[8] = {-1, 0, 1, -1, 1, -1, 0, 1};
long long lmax(long long a, long long b) {
  if (a < b)
    return b;
  else
    return a;
}
long long lmin(long long a, long long b) {
  if (a < b)
    return a;
  else
    return b;
}
long long gcd(long long a, long long b) {
  if (a < b) swap(a, b);
  if (b == 0) return a;
  if (a % b == 0) return b;
  return gcd(b, a % b);
}
long long Pow(long long n, long long k) {
  long long ret = 1;
  long long now = n;
  while (k > 0) {
    if (k & 1) ret *= now;
    now *= now;
    k /= 2;
  }
  return ret;
}
int main() {
  string s;
  cin >> s;
  int n = s.size();
  int num;
  for (long long i = 0; i < n; i++) {
    if (s[i] == 'S') {
      num = i;
      break;
    }
  }
  vector<int> v;
  int now = 1;
  for (long long i = num + 1; i < n; i++) {
    if (s[i] != s[i - 1]) {
      v.push_back(now);
      now = 1;
    } else {
      now++;
    }
  }
  v.push_back(now);
  int ans = 0;
  for (int i = 0; i < n; i += 2) {
    ans += min(v[i], v[i + 1]) * 2;
  }
  cout << n - ans << endl;
}
