#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;

#define INF (unsigned int)(!(int)0)

int main(){
    int n;
    cin >> n;
    int x1,y1,x2,y2;
    cin>>x1>>y1;
    int m1=0,m2=0;
    for(int i=1;i<n;i++){
        cin>>x2>>y2;
        if(i==1){
            if((x2-x1)==0){
                m1=INF;
            }
            else{
                if((y2-y1)==0){
                    m1=0;
                }
                else{
                    cout<<"NO";
                    return 0;
                }
            }
        }
        else{
            if((x2-x1)==0){
                m2=INF;
            }
            else{
                if((y2-y1)==0){
                    m2=0;
                }
                else{
                    cout<<"NO";
                    return 0;
                }
            }
            if(m1!=m2){
                cout<<"NO";
                return 0;
            }
        }
    }
    cout<<"YES";
    return 0;
}