CSES - HIIT Open 2019 - Just Solve It
  • Time limit: 1.00 s
  • Memory limit: 512 MB
A famous NP-complete problem is to detect if a graph can be colored using at most $k$ colors. In a valid coloring, each node is given a color and each edge connects two nodes with different colors.

In this problem, your task is to find out if a cycle graph of $n$ nodes can be colored using at most $k$ colors. A cycle graph consists of a single cycle.

Input

The only input line has two integers $n$ and $k$.

Output

Print "YES", if the graph can be colored, and "NO" otherwise.

Constraints
  • $3 \le n \le 10^9$
  • $1 \le k \le 10^9$
Example

Input:
5 3

Output:
YES