A11110. Two TVs
编程题
普及/提高-
知识点
题目描述
Polycarp is a great fan of television.
He wrote down all the TV programs he is interested in for today. His list contains $n$ shows, $i$ -th of them starts at moment $l_{i}$ and ends at moment $r_{i}$ .
Polycarp owns two TVs. He can watch two different shows simultaneously with two TVs but he can only watch one show at any given moment on a single TV. If one show ends at the same moment some other show starts then you can't watch them on a single TV.
Polycarp wants to check out all $n$ shows. Are two TVs enough to do so?
He wrote down all the TV programs he is interested in for today. His list contains $n$ shows, $i$ -th of them starts at moment $l_{i}$ and ends at moment $r_{i}$ .
Polycarp owns two TVs. He can watch two different shows simultaneously with two TVs but he can only watch one show at any given moment on a single TV. If one show ends at the same moment some other show starts then you can't watch them on a single TV.
Polycarp wants to check out all $n$ shows. Are two TVs enough to do so?
输入格式
The first line contains one integer $n$ ( $1<=n<=2·10^{5}$ ) — the number of shows.
Each of the next $n$ lines contains two integers $l_{i}$ and $r_{i}$ ( $0<=l_{i}<r_{i}<=10^{9}$ ) — starting and ending time of $i$ -th show.
Each of the next $n$ lines contains two integers $l_{i}$ and $r_{i}$ ( $0<=l_{i}<r_{i}<=10^{9}$ ) — starting and ending time of $i$ -th show.
输出格式
If Polycarp is able to check out all the shows using only two TVs then print "YES" (without quotes). Otherwise, print "NO" (without quotes).
输入输出样例
输入 #1
3 1 2 2 3 4 5
输出 #1
YES
输入 #2
4 1 2 2 3 2 3 1 2
输出 #2
NO