import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        
        int n = in.nextInt();
        int []xx=new int[n];
        int []yy=new int[n];
        for(int a0 = 0; a0 < n; a0++){
            int x = in.nextInt();
            int y = in.nextInt();
            xx[a0]=x;
            yy[a0]=y;
        }
        boolean flagx=true;
        boolean flagy=true;
         for(int i = 1; i < n; i++){
            if(xx[0]!=xx[i]){
                flagx=false;
                break;
            }
        }
        for(int i = 1; i < n; i++){
            if(yy[0]!=yy[i]){
                flagy=false;
                break;
            }
        }
        if(flagx||flagy){
            System.out.println("YES");
        }
        else{
            System.out.println("NO");
        }
            
        
    }
}