#!/bin/python3

import sys
n = int(input().strip())
X=[0]*n
Y=[0]*n
k=0
for i in range(n):
    x,y = input().strip().split(' ')
    X[i],Y[i] = [int(x),int(y)]
    '''
    if(i>2):
        area=X[0]*(Y[1]-Y[i])+X[1]*(Y[i]-Y[0])+X[2]*(Y[0]-Y[1])
        if(area!=0):
            print("NO")
            k=9
            break
if(k==0):
    print("YES")
    '''
if(max(X)==min(X) or max(Y)==min(Y)):
    print("YES")
else:
        print("NO")