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[] x = new int[n];
        int[] y = new int[n];
        
        for(int a0 = 0; a0 < n; a0++){
            x[a0] = in.nextInt();
            y[a0] = in.nextInt();
        }
        
        Arrays.sort(x);
        Arrays.sort(y);
        
        boolean sameX = true;
        boolean sameY = true;
        
        for(int i = 0; i < n - 1; i++) {
           if(sameX && x[i] != x[i + 1]) {
               sameX = false;
           }
           
            if(sameY && y[i] != y[i+1]) {
               sameY = false;
            }
           
        }
        
        if(sameX || sameY) {
            System.out.println("YES");
            
        } else {
            System.out.println("NO");
        }
    }
}