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 s = new Scanner(System.in);
		int n = s.nextInt();

		int data[][] = new int[n][2];
		for (int i = 0; i < n; i++)
		{
			data[i][0] = s.nextInt();
			data[i][1] = s.nextInt();
		}

		if (data[1][0] == data[0][0])
		{
			int che = 0;
			for (int i = 2; i < n; i++)
			{
				if (data[i][0] != data[0][0])
				{
					che = 1;
					break;
				}
			}
			if (che == 1)
				System.out.println("NO");
			else
				System.out.println("YES");

		} else
		{
			double slope = (double) (data[1][1] - data[0][1])
					/ (double) (data[1][0] - data[0][0]);

			int che = 0;
			for (int i = 2; i < n; i++)
			{
				double slope1 = (double) (data[i][1] - data[0][1])
						/ (double) (data[i][0] - data[0][0]);

				if (slope != slope1)
				{
					che = 1;
					break;
				}
			}
			if (che == 1)
				System.out.println("NO");
			else
				System.out.println("YES");
		}

	}

}