#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define f(i,n) for(ll i=0;i<n;i++)
#define m(a,b,c) max(a,max(b,c))
#define N ll n;cin >> n;
#define Nk ll n,k;cin >> n >> k;
#define A ll a[n];f(i,n) cin >> a[i];
#define FAST_IO ios_base::sync_with_stdio(false), cin.tie(nullptr);
#define YES cout<<"YES"<<endl;
#define NO cout<<"NO"<<endl;
#define S string s;cin>>s;
#define pb push_back

int main()
{
   FAST_IO;
   N;
   if(2*n<=100)
   {
       YES;
   }
   else 
   NO;
   return 0;
}