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题目描述

Problem Statement

Snuke is playing a puzzle game.
In this game, you are given a rectangular board of dimensions R × C, filled with numbers. Each integer i from 1 through N is written twice, at the coordinates (x_{i,1},y_{i,1}) and (x_{i,2},y_{i,2}).
The objective is to draw a curve connecting the pair of points where the same integer is written, for every integer from 1 through N.
Here, the curves may not go outside the board or cross each other.
Determine whether this is possible.

Input

Input is given from Standard Input in the following format:
R C N
x_{1,1} y_{1,1} x_{1,2} y_{1,2}
:
x_{N,1} y_{N,1} x_{N,2} y_{N,2}

Output

Print YES if the objective is achievable; print NO otherwise.

Constraints

  • 1 ≤ R,C ≤ 10^8
  • 1 ≤ N ≤ 10^5
  • 0 ≤ x_{i,1},x_{i,2} ≤ R(1 ≤ i ≤ N)
  • 0 ≤ y_{i,1},y_{i,2} ≤ C(1 ≤ i ≤ N)
  • All given points are distinct.
  • All input values are integers.

Sample Input 1

4 2 3
0 1 3 1
1 1 4 1
2 0 2 2

Sample Output 1

YES

The above figure shows a possible solution.

Sample Input 2

2 2 4
0 0 2 2
2 0 0 1
0 2 1 2
1 1 2 1

Sample Output 2

NO

Sample Input 3

5 5 7
0 0 2 4
2 3 4 5
3 5 5 2
5 5 5 4
0 3 5 1
2 2 4 4
0 5 4 1

Sample Output 3

YES

Sample Input 4

1 1 2
0 0 1 1
1 0 0 1

Sample Output 4

NO

输入格式

见题面 Input 部分

输出格式

见题面 Output 部分

样例输入
4 2 3 0 1 3 1 1 1 4 1 2 0 2 2
样例输出
YES