#include <bits/stdc++.h>
using namespace std;
//#include <atcoder/all>
//using namespace atcoder;
using ll=long long;
using Graph=vector<vector<int>>;
#define MAX 1000000
#define MOD 1000000007
//#define INF 1000000000
#define INF 1000000000000000000

int main(){
  string N;
  cin>>N;
  if(N.size()==2){
    cout<<"Yes"<<endl;
  }else{
    cout<<"No"<<endl;
  }
}