B. Pancakes (Easy Version)
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

An opponent's P.E.K.K.A. with $$$a_2$$$ attack points and $$$h_2$$$ health points is coming straight for your tower! You quickly deploy your own P.E.K.K.A., with $$$a_1$$$ attack points and $$$h_1$$$ health points. The P.E.K.K.A.'s will battle each other, swinging at each other at the exact time every second until one or both dies. Every swing, your P.E.K.K.A. will remove $$$a_1$$$ health points from your opponent's, and your opponent's P.E.K.K.A. will remove $$$a_2$$$ health points from yours. A P.E.K.K.A. dies when it reaches 0 or less health points. If your P.E.K.K.A. can survive the battle and destroy the opponent's, output "YES". Otherwise, output "NO."

Input

The input contains four integers $$$a_1$$$, $$$h_1$$$, $$$a_2$$$, $$$h_2$$$ ($$$1 \le a_1, h_1, a_2, h_2 \le 10^{9}$$$).

Output

If your P.E.K.K.A. can kill the opponent's P.E.K.K.A. and stay alive, output "YES". Else, output "NO".

Examples
Input
5 20 3 30
Output
YES
Input
3 12 2 20
Output
NO
Input
9 9 9 9
Output
NO
Note

In the first test case, your P.E.K.K.A. wins after 6 swings. It survive on 2 health points. In the second test case, your P.E.K.K.A. dies after 6 swings. The opponent P.E.K.K.A. still has 2 health points. In the third test case, both of your P.E.K.K.A.'s die after the first swing. You need to survive, so the answer is "NO".