import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.StringTokenizer;

public class PointsOnALine {

	public static void main(String[] args) throws IOException {
		BufferedReader reader=new BufferedReader(new InputStreamReader(System.in));
		int n=Integer.parseInt(reader.readLine());
		ArrayList<Integer> x=new ArrayList<>(), y=new ArrayList<>();
 		while(n-- >0){
			StringTokenizer str=new StringTokenizer(reader.readLine());
			int x1=Integer.parseInt(str.nextToken());
			int y1=Integer.parseInt(str.nextToken());
			if(!x.contains(x1)){
				x.add(x1);
			}
			if(!y.contains(y1)){
				y.add(y1);
			}
		}
 		if(x.size()==1 || y.size()==1){
 			System.out.println("YES");
 		}
 		else{
 			System.out.println("NO");
 		}
	}
}