#include <stdio.h>
main ()
{
    int n;
    scanf ("%d", &n);
    int x[n], y[n];
    int flag=0;
    for (int i=0; i<=n-1; i++)
    scanf ("%d %d", &x[i], &y[i]);
    if (x[1]-x[0]!=0){
        float m=(y[1]-y[0])/(x[1]-x[0]);
        float m1=0;
        int flag=0;
        for (int i=2; i<=n-1; i++){
            m1=(y[i]-y[0])/(x[i]-x[0]);
            if (m1==m)
            flag+=1;
        }
        if (flag==n-2)
        printf ("YES");
        else
        printf ("NO");
    }
    else{
        int flag=0;
        for (int i=2; i<=n-1; i++){
            if (x[i]-x[0]==0)
            flag+=1;
        }
        if (flag==n-2)
        printf ("YES");
        else
        printf ("NO");
    }
}