#include <bits/stdc++.h>

#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
const int INF = 1001001001;
const ll LINF = 1001001001001001001;
const ll MOD = 998244353;

int main() {
  string s;cin>>s;
  if(s.at(0)==s.at(1)&&s.at(1)!=s.at(2)) cout << "Yes" << endl;
  else cout << "No" << endl;

  exit(0);
}