305054: CF958E1. Guard Duty (easy)

Memory Limit:256 MB Time Limit:1 S
Judge Style:Text Compare Creator:
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Description

Guard Duty (easy)

题目描述

The Rebel fleet is afraid that the Empire might want to strike back again. Princess Heidi needs to know if it is possible to assign $ R $ Rebel spaceships to guard $ B $ bases so that every base has exactly one guardian and each spaceship has exactly one assigned base (in other words, the assignment is a perfect matching). Since she knows how reckless her pilots are, she wants to be sure that any two (straight) paths – from a base to its assigned spaceship – do not intersect in the galaxy plane (that is, in 2D), and so there is no risk of collision.

输入输出格式

输入格式


The first line contains two space-separated integers $ R,B(1<=R,B<=10) $ . For $ 1<=i<=R $ , the $ i+1 $ -th line contains two space-separated integers $ x_{i} $ and $ y_{i} $ ( $ |x_{i}|,|y_{i}|<=10000 $ ) denoting the coordinates of the $ i $ -th Rebel spaceship. The following $ B $ lines have the same format, denoting the position of bases. It is guaranteed that no two points coincide and that no three points are on the same line.

输出格式


If it is possible to connect Rebel spaceships and bases so as satisfy the constraint, output Yes, otherwise output No (without quote).

输入输出样例

输入样例 #1

3 3
0 0
2 0
3 1
-2 1
0 3
2 2

输出样例 #1

Yes

输入样例 #2

2 1
1 0
2 2
3 1

输出样例 #2

No

说明

For the first example, one possible way is to connect the Rebels and bases in order. For the second example, there is no perfect matching between Rebels and bases.

Input

题意翻译

在一个二维平面中,有 $R$ 艘飞船和 $B$ 个基地,给出他们的坐标,判断是否存在一种方案使得所有飞船和基地都成功连接且任意两条直线不会相交。

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