#!/bin/python3

import sys


n = int(input().strip())
x_list = []
y_list = []
for a0 in range(n):
    x,y = input().strip().split(' ')
    x,y = [int(x),int(y)]
    x_list.append(x)
    y_list.append(y)
    
is_same_line = 'NO'
for l in [x_list, y_list]:
    if sum(l)/len(l) == l[0]:
        is_same_line = 'YES'
print(is_same_line)