using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
class Solution {

    static void Main(String[] args) {
        int n = Convert.ToInt32(Console.ReadLine());
        int[] xx = new int[n];
        int[] yy = new int[n];
        for(int a0 = 0; a0 < n; a0++){
            string[] tokens_x = Console.ReadLine().Split(' ');
            xx[a0] = Convert.ToInt32(tokens_x[0]);
            yy[a0] = Convert.ToInt32(tokens_x[1]);
        }
        
        bool xxx = true;
        bool yyy = true;
        for (int i = 1; i < n; i++) {
            if (xx[i] != xx[0])
                xxx = false;
            if (yy[i] != yy[0])
                yyy = false;
        }
        
        Console.WriteLine(xxx || yyy ? "YES" : "NO");
    }
}