#include "bits/stdc++.h"
using namespace std;
int n;
int x , y;
map < int , int > m1;
map < int , int > m2;
int main(){
	m1.clear();
	m2.clear();
	scanf("%d" , &n);
	while(n--){
		scanf("%d %d" , &x , &y);
		m1[x];
		m2[y];
	}
	if(m1.size() <= 1 || m2.size() <= 1){
		cout << "YES\n";
	}
	else{
		cout << "NO\n";
	}
}