vcd
题号：NC17423
时间限制：C/C++/Rust/Pascal 2秒，其他语言4秒
空间限制：C/C++/Rust/Pascal 256 M，其他语言512 M
64bit IO Format: %lld

题目描述

Kanade has an infinity set H contain all of sets such as {(x,y)|x>=a,l<=y<=r}  (a,l,r are arbitrary real numbers)
A point set S is good if and only if for each subset T of S there exist h in H satisfy 

Now kanade has n distinct points and she want to know how many non-empty subset of these points is good.

You need to output the answer module 998244353

输入描述:

The first line has one integer n

Then there are n lines,each line has two integers x,y denote a point (x,y)

输出描述:

Output the answer module 998244353
示例1

输入

复制 
3
1 1
2 2
3 3

输出

复制 
6

备注:

1<=n<=10^5

1<=x, y<=10^9