# include <bits/stdc++.h>
using namespace std;
vector <int> vc;
int main (){
    int n,k;
    cin >> n>>k;
    for (int i = 1;i <= n;i+=2){
        vc.push_back(i);
    }
    if (vc.size() < k) cout << "NO";
    else cout << "YES";
}
