#!/bin/python

n = int(raw_input())
li = []
for i in xrange(n):
  li.append(map(int,raw_input().split()))
if sum([ i[0] for i in li]) / float(n) == float(li[0][0]) or sum([ i[1] for i in li]) / float(n) == float(li[1][1]):
  print "YES"
else:
  print "NO"