#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;
    float x1, y1, x2, y2;
    cin>>x1>>y1;
    cin>>x2>>y2;
    float slope;
    if(x2 - x1 == 0) {
        slope = 10000;
    } else {
      slope = (y2 - y1) / (x2 - x1);
    }
    bool isLinear = true;
    for(int a0 = 0; a0 < n - 2; a0++){
        cin>>x2>>y2;
        float slopeNow;
        if(x2 - x1 == 0) {
            slopeNow = 10000;
        } else {
          slopeNow = (y2 - y1) / (x2 - x1);
        }
        if(slope != slopeNow) isLinear = false;
    }
    isLinear ? cout<<"YES"<<endl : cout<<"NO"<<endl;
    return 0;
}