#include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>

using namespace std;


int main() {

	int n;
	cin>>n;
	int counter= n;
	vector<int> x_points;
	vector<int> y_points;
	while(n--)
	{
		int x,y;
		cin>>x>>y;
		x_points.push_back(x);
		y_points.push_back(y);
		
	
	}
	int st_x=x_points[0];
	int st_y=y_points[0];
	
	if((count(x_points.begin(),x_points.end(),st_x)==x_points.size()) || 
	(count(y_points.begin(),y_points.end(),st_y)==y_points.size()))
	cout<<"YES"<<endl;
	else
	cout<<"NO"<<endl;
	
	
	
	
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    return 0;
}