Problem:
Score : 100 points

Problem Statement

Determine if we can choose K different integers between 1 and N (inclusive) so that no two of them differ by 1.

Constraints

1\leq N,K\leq 100

N and K are integers.

Input

Input is given from Standard Input in the following format:

N K

Output

If we can choose K integers as above, print YES; otherwise, print NO.

Sample Input 1

3 2

Sample Output 1

YES

We can choose 1 and 3.

Sample Input 2

5 5

Sample Output 2

NO

Sample Input 3

31 10

Sample Output 3

YES

Sample Input 4

10 90

Sample Output 4

NO

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Runtime Error)

public class Main {
 
        public static void main(String[] args) {
                int n = Integer.parseInt(args[0]);
                int k = Integer.parseInt(args[1]);
                boolean resultFlg = false;
 
                int cnt = 0;
                for(int i=0; i<n; i+=2) {
                        cnt ++;
                        if(k <= cnt) resultFlg = true;
                }
 
                if(resultFlg) System.out.println("Yes");
                else System.out.println("No");
        }
 
}