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

public class Solution {

    public static void checkPoints(int[] xPoints, int[] yPoints) {
        boolean xLine = true;
        boolean yLine = true;
        
        for (int i = 0; i < xPoints.length; i++) {
            for (int j = 0; j <xPoints.length; j++) {
                if (xPoints[i] != xPoints[j]) {
                    xLine = false;
                }
                if (yPoints[i] != yPoints[j]) {
                    yLine = false;
                }
            }
        }
        
        if (xLine || yLine) {
            System.out.print("YES");
        }
        else {
            System.out.print("NO");
        }
        
    }

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        int[] xPoints = new int[n];
        int[] yPoints = new int[n];
        for(int a0 = 0; a0 < n; a0++){
            int x = in.nextInt();
            int y = in.nextInt();

            xPoints[a0] = x;
            yPoints[a0] = y;
        }
        checkPoints(xPoints, yPoints);
    }
}