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();
        ArrayList<Integer> xCoords = new ArrayList<Integer>();
        ArrayList<Integer> yCoords = new ArrayList<Integer>();
        int initX=0,initY = 0;
        boolean sameLine = true,horizontal=true,vertical=true;
        for(int a0 = 0; a0 < n; a0++){
        	int x = in.nextInt();
            int y = in.nextInt();
            xCoords.add(x);
            yCoords.add(y);
        }
        in.close();
        
        for(int i=0;i<xCoords.size();i++){
        	if(i==0) initX = xCoords.get(i);
        	else{
        		if(xCoords.get(i) != initX){
        			horizontal = false;
        			break;
        		}
        	}
        }
        if(!horizontal){
        	for(int i=0;i<yCoords.size();i++){
            	if(i==0) initY = yCoords.get(i);
            	else{
            		if(yCoords.get(i) != initY){
            			vertical = false;
            			break;
            		}
            	}
            }
        	if(vertical){
        		System.out.println("YES");
        	}else{
        		System.out.println("NO");
        	}
        }else{
        	System.out.println("YES");
        }
	}
    
}