You are choreographing a circus show with various animals. For one act, you are given two kangaroos on a number line ready to jump in the positive direction (i.e, toward positive infinity).

The first kangaroo starts at location $x\mbox{1}$ and moves at a rate of $\mbox{v1}$ meters per jump.
The second kangaroo starts at location $x2$ and moves at a rate of $v2$ meters per jump.

You have to figure out a way to get both kangaroos at the same location at the same time as part of the show. If it is possible, return YES, otherwise return NO.

Example

$x1=2$

$v1=1$

$x2=1$

$v2=2$

After one jump, they are both at $x=3$, ($x1+v1=2+1$, $x2+v2=1+2$), so the answer is YES.

Function Description

Complete the function kangaroo in the editor below.

kangaroo has the following parameter(s):

int x1, int v1: starting position and jump distance for kangaroo 1
int x2, int v2: starting position and jump distance for kangaroo 2

Returns

string: either YES or NO

Input Format

A single line of four space-separated integers denoting the respective values of $x\mbox{1}$, $\mbox{v1}$, $x2$, and $v2$.

Constraints

$0\leq x1<x2\leq10000$
$1\leq v1\leq10000$
$1\leq v2\leq10000$

Sample Input 0
0 3 4 2

Sample Output 0
YES

Explanation 0

The two kangaroos jump through the following sequence of locations:

From the image, it is clear that the kangaroos meet at the same location (number $12$ on the number line) after same number of jumps ($\begin{array}{c}4\end{array}$ jumps), and we print YES.

Sample Input 1
0 2 5 3

Sample Output 1
NO

Explanation 1

The second kangaroo has a starting location that is ahead (further to the right) of the first kangaroo's starting location (i.e., $x_2>x_1$). Because the second kangaroo moves at a faster rate (meaning $v_2>v_1$) and is already ahead of the first kangaroo, the first kangaroo will never be able to catch up. Thus, we print NO.

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