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 [,] a = new int[n,2]; 
        for(int a0 = 0; a0 < n; a0++){
            string[] tokens_x = Console.ReadLine().Split(' ');
            int x = Convert.ToInt32(tokens_x[0]);
            int y = Convert.ToInt32(tokens_x[1]);
            a[a0, 0] = x;
            a[a0, 1] = y;
        }
        
        bool v = true;
        bool h = true;
        for(int a0 = 0; a0 < n -1; a0++){
            if(h && a[a0, 0] == a[a0 + 1, 0])
                h = true;
            else
                h = false;
            if(v && a[a0, 1] == a[a0 + 1, 1])
                v = true;
            else
                v = false;
        }
        if (h || v)
            Console.WriteLine("YES");
        else
            Console.WriteLine("NO");
    }
}