#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>

int main(){
    int n; 
    scanf("%d",&n);
    
    int flag=1;
    float a,b,x,y;
    scanf ("%f %f",&a,&b);
    scanf ("%f %f",&x,&y);
    float slope;
    float right=0;
    if (x-a==0){right=1;}
    else slope=(y-b)/(x-a);
    if (right==1){
        for (int i=0;i<n-2;i++){
            scanf ("%f %f",&x,&y);
            if (x-a!=0){flag=0;break;}
        }
    }
    else{
    for (int i=0;i<n-2;i++){
           scanf ("%f %f",&x,&y);
            if ((y-b)/(x-a)!=slope){flag=0;break;}
    }}
    if (flag==1)printf ("YES");
    else printf ("NO");
   
    
    
    return 0;
}