#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <string>
#include <bitset>
#include <cstdio>
#include <limits>
#include <vector>
#include <climits>
#include <cstring>
#include <cstdlib>
#include <fstream>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <unordered_map>

using namespace std;


int main(){
    int n;
    cin >> n;
    int xa,ya;
    vector<int> x;
    vector<int> y;
    for(int a0 = 0; a0 < n; a0++){
        
        cin >> xa >> ya;
        x.push_back(xa);
        y.push_back(ya);
        //cout<<"x"<<xa;
        //cout<<"y"<<ya;
        
        
    }
    int m1,m2;
    int k1,k2;
    int x1,x0,y1,y0;
    x1=x[1];
    y1=y[1];
    x0=x[0];
    y0=y[0];
    int flag=1;
    k1=(y1-y0);
    k2=(x1-x0);
    
   // cout<<"k1 = "<<k1<<", k2 = "<<k2<<endl;
    if((y1-y0)==0 || (x1-x0)==0){
        for(int i=2;i<x.size();i++){
           m1=(y[i]-y[i-1]);
           m2=(x[i]-x[i-1]);
           // cout<<"m1 = "<<m1<<", m2 = "<<m2<<endl;
            if((k1==0 && m1==0)||(k2==0 && m2==0)){
                flag=1;
            
            } else {
                flag=0;
                break;
            }
           
        }
         if(flag==1){
             cout<<"YES"<<endl;
         } else {
             cout<<"NO"<<endl;
         }  
    } else {
        cout<<"NO"<<endl;
    }
    
    
    
    return 0;
}