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();
        int[] xArr = new int[n];
        int[] yArr = new int[n];
        for(int a0 = 0; a0 < n; a0++){
            xArr[a0] = in.nextInt();
            yArr[a0] = in.nextInt();
        }
        double slope =Integer.MAX_VALUE;
        double tempSlope =Integer.MAX_VALUE;
        boolean result = true;
        if(n<=2){
            System.out.println("YES");
        }
        else{
            if(xArr[0]!=xArr[1]){
                slope = Math.abs((yArr[1]-yArr[0])/(xArr[1]-xArr[0]));
            }
            for(int i=2;i<n;i++){
                if(xArr[0]!=xArr[i]){
                    tempSlope = Math.abs((yArr[i]-yArr[0])/(xArr[i]-xArr[0]));
                }
                else{
                    tempSlope = Integer.MAX_VALUE;
                }
                if(slope!=tempSlope){
                    result = false;
                }
            }
            if(result){
                System.out.println("YES");
            }
            else{
                 System.out.println("NO");
            }
        }
    }
}