#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;
    int flag = 0;
    cin >> n;
    
    for(int a0 = 0; a0 < n; a0++){
        
        int x;
        int y;
        float slope1;
        float slope2;
        
        
        
        if(a0 == 0)
            cin>>x>>y;
        
        else if(a0 ==1)
            {
            int x1,y1;
            cin>>x1>>y1;
            slope1 = float(y-y1)/float(x-x1);
            
            
        }
        
      else{
          int x2, y2;
            cin>>x2>>y2;
            slope2 = float(y-y2)/float(x-x2);
      
          
          if(slope1 != slope2)
              {
              cout<<"NO";
              return 0;
          }
            
        }
        
        
    }
  
        cout<<"YES";
    
    return 0;
}