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 x=0, y=0, prevX, prevY, slope=0, pSlope;
        boolean inLn = true;
        
        for(int a0 = 0; a0 < n; a0++){
            if (a0 == 0) {
                x = in.nextInt();
                y = in.nextInt();
                continue;
            }
            prevX = x;
            prevY = y;
            x = in.nextInt();
            y = in.nextInt();
            
            pSlope = slope;
            
            if (y != prevY)
                slope = (x-prevX)/(y-prevY);
            else 
                continue;
            if (a0 == 1) continue;
            
            if (pSlope != slope) {
                inLn = false;
            }
        }
        
        if (inLn)
            System.out.println("YES");
        else
            System.out.println("NO");
        
    }
}