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

     static void Main(String[] argv){
        int  N = Convert.ToInt32(Console.ReadLine());

        int[] mempointx = new int[22];
        int[] mempointy = new int[22];

        for (int  i = 0; i < N; i++)
        {
            string[] point = Console.ReadLine ().Split (' ');

            mempointx[Convert.ToInt32(point[0])+10]++;

            mempointy[Convert.ToInt32(point[1])+10]++;

        }
        bool found = false;
        for (int i = 0; i <= 20; i++)
            if (mempointx[i] == N)
            {   
                Console.WriteLine("YES");
                found = true;
                break;

            }
        if(!found)
            for (int i = 0; i <= 20; i++)
                if (mempointy[i] == N)
                {   
                    Console.WriteLine("YES");
                    found = true;
                    break;

                }
            

        if(!found)
            Console.WriteLine("NO");

    }
}