Kanade has an infinity set H contain all of sets such as {(x,y)x=a,l 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 nThen 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

备注:

11=x, y=10^9