#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  int n = (int)s.size();
  int ans = 1;
  for (int i = 0; i < n - 1; i++) {
    if (s[i] == s[i + 1]) {
      i += 1;
    }
    ans++;
  }
  cout << ans;
}
