#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
#define Pr pair<ll,ll>
#define Tp tuple<ll,ll,ll>
using Graph = vector<vector<int>>;

ll mod = 1000000007;

int main() {
    ll N; cin >> N;
    string ans = "No";
    if(10<=N&&N<=99) ans = "Yes";
    cout << ans << endl;
}