#include <bits/stdc++.h>
using namespace std;
const long long LINF = 1e18;
const int INF = 1e9 * 2;
const int MOD = 1e9 + 7;
const int modulo = 1e8;
const int nax = 2 * 1e5;
void solve() {
  string s;
  cin >> s;
  int cur = 1;
  s += s;
  int ans = 0;
  for (int i = 1; i < (int)s.size(); i++) {
    if (s[i] != s[i - 1])
      cur++;
    else {
      ans = max(ans, cur);
      cur = 1;
    }
  }
  ans = max(ans, cur);
  cout << min(ans, (int)s.size() / 2);
}
int main() {
  ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  int test_case;
  test_case = 1;
  for (; test_case > 0; test_case--) {
    solve();
  }
}
