Ghost of Kyiv

Limits: 1 sec., 256 MiB

This statement was translated automatically from Ukrainian.

Few people know that the Ghost of Kyiv is actually Zenik. Zenik’s plane is equipped with missiles that deal \(a\) damage. Zenik’s plane also has \(b\) health. No one knows whether the Ghost of Kyiv is still alive or not. However, it is known that Zenik was alive until the last time there was an enemy attack. In that air battle, Zenik was opposed by \(n\) enemy planes. It is known that the \(i\)-th plane was equipped with missiles dealing \(d_i\) damage, and the health of this plane was \(h_i\). Zenik is a very skilled pilot, and therefore he lured out the enemy planes one by one in a given order.

The battle between two planes proceeds as follows: the planes take turns firing missiles at each other until the health of one of the planes is no longer positive. Zenik controls his plane much better than any enemy pilot, so he will always fire his missiles first.

Tell whether Zenik’s plane remained intact after all the air battles?

Input

The first line gives three integers \(n\), \(a\) and \(b\) — the number of enemy planes, the damage of Zenik’s plane missiles, and the health of Zenik’s plane.

The next \(n\) lines each specify two integers \(d_i\) and \(h_i\) — the damage of the \(i\)-th enemy plane’s missiles and its health.

Output

Output Yes if Zenik’s plane survived and No otherwise.

Constraints

\(1 \le n\le 10^{3}\),

\(1 \le a\le 10^{3}\),

\(1 \le b\le 10^{9}\),

\(0 \le d_i,h_i \le 10^{3}\),

Samples