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();
        
        List<Point> list = new ArrayList<>();
        for(int a0 = 0; a0 < n; a0++){
            int x = in.nextInt();
            int y = in.nextInt();
            list.add(new Point(x, y));
        }
        
        boolean result = solve(list);
        System.out.println(result? "YES" : "NO");
    }
    
    static boolean solve(List<Point> list) {
        for (int x = -10; x <= 10; x++) {
            boolean valid = true;
            for (Point point : list) {
                if (point.x != x) {
                    valid = false;
                }
            }
            
            if (valid)
                return true;
        }
        
        for (int y = -10; y <= 10; y++) {
            boolean valid = true;
            for (Point point : list) {
                if (point.y != y) {
                    valid = false;
                }
            }
            
            if (valid)
                return true;
        }
        
        return false;
    }
    
    static class Point {
        int x, y;
        
        public Point(int x, int y) {
            this.x = x;
            this.y = y;
        }
    }
}