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(), memX = 0, memY = 0;
        boolean isCollinear = true;
        boolean isX = true, isY = true;
        for(int a0 = 0; a0 < n; a0++){
            int x = in.nextInt();
            int y = in.nextInt();
            if (a0 == 0) {
                memX = x;
                memY = y;
                continue;
            }    
            if (x != memX) 
                isX = false;
            if (y != memY)  
                isY = false;
        }
        if (isX || isY) 
            System.out.println("YES");
        else
            System.out.println("NO");
    }
}