#include <bits/stdc++.h>

using namespace std;
#define rep(i, n, o) for(int i = o;i < (n);i++)
#define ou(x) cout << x << endl
#define ll long long
#define re return 0

int main(){
    string s;
    cin >> s;
    if(s.length() == 2) ou("Yes");
    else ou("No");
    re;
}