Vanishing Pitch

Source: AtCoder

Problem Statement

A ball moves at constant speed $V$ m/s. It is invisible from $T$ seconds through $S$ seconds after the throw, inclusive. The batter must hit it when it is exactly $D$ meters away. Determine whether the ball is visible then.

Input

One line contains $V$, $T$, $S$, and $D$.

Output

Print Yes if the batter can hit the ball; otherwise print No.

Subtasks

• Subtask 1 (100%): $1 \le V \le 1000$; $1 \le T<S \le 1000$; $1 \le D \le 1000$

Examples

Example 1

Input

10 3 5 20

Output

Yes

Explanation

For the sample values 10, 3, 5, 20, evaluating the conditions in the statement gives Yes. Therefore the program prints the shown output.

Example 2

Input

10 3 5 30

Output

No

Explanation

For the sample values 10, 3, 5, 30, evaluating the conditions in the statement gives No. Therefore the program prints the shown output.