using System;
using System.Globalization;
using System.IO;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;
using System.Threading;

namespace Codeforces
{
    class Program : ProgramBase
    {
        private const long commonMod = 1000000007;
        
        static void Main(string[] args)
        {
            var p = new Program();
            var x = p.Get();
            p.Out(x);
        }

        object Get()
        {
            checked
            {
                var n = ReadIntToken();
                var points = new int[n][];
                for (int i = 0; i < n; i++)
                {
                    points[i] = ReadInts();
                }
                var y = points[0][1];
                var isEqY = true;
                for (int i = 1; i < n; i++)
                {
                    isEqY &= points[i][1] == y;
                }
                var x = points[0][0];
                var isEqX = true;
                for (int i = 1; i < n; i++)
                {
                    isEqX &= points[i][0] == x;
                }
                return (isEqX || isEqY) ? "YES" : "NO";
            }

        }
        public static class Struct
        {
            public static Pair<T1, T2> Create<T1,T2>(T1 item1, T2 item2)
            {
                return new Pair<T1, T2> { Item1 = item1, Item2 = item2 };
            }
        }

        public struct Pair<T1, T2>
        {
            public T1 Item1 { get; set; }
            public T2 Item2 { get; set; }
        }

        class Automata
        {
            bool[] terminals;
            public int sigma;
            public int len;
            public int[,] jumps;

            public void Create()
            {
                var a = ReadInts();
                len = a[0];
                sigma = a[2];
                var ts = ReadInts();
                terminals = new bool[len];
                for (int i = 0; i < ts.Length; i++)
                    terminals[ts[i]] = true;
                jumps = new int[len, sigma];
                for (int i = 0; i < len * sigma; i++)
                {
                    var b = Console.ReadLine().Split(' ');
                    jumps[Convert.ToInt32(b[0]), b[1][0] - 'a'] = Convert.ToInt32(b[2]);
                }
            }
            protected int[] ReadInts()
            {
                return Console.ReadLine().Split(' ').Select(x => Convert.ToInt32(x)).ToArray();
            }

            public bool IsTerminal(int s)
            {
                return terminals[s];
            }
        }
    }

    abstract class ProgramBase
    {
        bool? prod = null;
        StreamReader f;
        Queue<string> tokens;
        protected string FileName { private get; set; }

        protected string Read()
        {
            if (f == null)
                f = string.IsNullOrEmpty(FileName)
                    ? new StreamReader(Console.OpenStandardInput())
                    : new StreamReader((GetProd() ? "" : "c:\\dev\\") + FileName);
            return f.ReadLine();
        }

        protected int ReadInt()
        {
            return int.Parse(Read());
        }

        protected int ReadIntToken()
        {
            if (tokens == null || tokens.Count == 0)
                tokens = new Queue<string>(Read().Split(' '));
            return int.Parse(tokens.Dequeue());
        }

        protected int[] ReadInts()
        {
            var tokens = Read().Split(' ');
            var result = new int[tokens.Length];
            for (int i = 0; i < tokens.Length; i++)
                result[i] = int.Parse(tokens[i]);
            return result;
        }


        protected long ReadLongToken()
        {
            if (tokens == null || tokens.Count == 0)
                tokens = new Queue<string>(Read().Split(' '));
            return long.Parse(tokens.Dequeue());
        }

        protected long ReadLong()
        {
            return Convert.ToInt64(Read());
        }

        protected long[] ReadLongs()
        {
            var tokens = Read().Split(' ');
            var result = new long[tokens.Length];
            for (int i = 0; i < tokens.Length; i++)
                result[i] = long.Parse(tokens[i]);
            return result;
        }

        public void Out(object r)
        {
            if (string.IsNullOrEmpty(FileName))
                Console.WriteLine(r);
            else if (GetProd())
                File.WriteAllText(FileName, r.ToString());
            else
                Console.WriteLine(r);
        }

        private bool GetProd()
        {

            if (!prod.HasValue)
                try
                {
                    prod = Environment.MachineName != "RENADEEN-W7";
                }
                catch (Exception)
                {
                    prod = true;
                }
            return prod.Value;
        }
    }

    public static class Huj
    {
        public static T MinBy<T>(this IEnumerable<T> source, Func<T, double> func) where T : class
        {
            T result = null;
            var min = double.MaxValue;
            foreach (var item in source)
            {
                var current = func(item);
                if (min > current)
                {
                    min = current;
                    result = item;
                }
            }
            return result;
        }

        public static T MaxBy<T>(this IEnumerable<T> source, Func<T, double> func, T defaultValue = default(T))
        {
            T result = defaultValue;
            var max = double.MinValue;
            foreach (var item in source)
            {
                var current = func(item);
                if (max < current)
                {
                    max = current;
                    result = item;
                }
            }
            return result;
        }

        public static string JoinStrings(this IEnumerable<string> source, string delimeter)
        {
            return string.Join(delimeter, source.ToArray());
        }

        public static string JoinStrings(this IEnumerable<int> source, string delimeter)
        {
            return source.Select(x => x.ToString()).JoinStrings(delimeter);
        }
    }
}