#include<iostream>
#include<string>
#include<algorithm>
#include<cctype>
#include<set>
#include<bitset>
#include<math.h>
#include<map>
#include<queue>
#include<iomanip>
using namespace std;

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