#include <bits/stdc++.h> #include <atcoder/all> #define rep(i, n) for (int i=0; i<(n); i++) #define len(x) (int)(x).size() #define all(x) x.begin(), x.end() #define rall(x) x.rbegin(), x.rend() using namespace std; using namespace atcoder; using ll = long long; using mint9 = atcoder::modint998244353; using mint10 = atcoder::modint1000000007; int main() { ios::sync_with_stdio(false); cin.tie(0); string S; cin >> S; if(S[0] == S[1] && S[1] != S[2]) cout << "Yes" << endl; else cout << "No" << endl; return 0; }