#include<iostream>
using namespace std;
int main()
{
    int n;
    bool flag = true;
    cin>>n;
    float x[n], y[n], m1, m2;
    for(int i = 0; i < n; i++)
        cin>>x[i]>>y[i];
    m1 = (y[1] - y[0])/(x[1] - x[0]);
    for(int i = 2; i < n; i++)
    {
        m2 = (y[i] - y[0])/(x[i] - x[0]);
        if(m1!=m2)
        {
            flag =  false;
            break;
        }
        m1 = m2;
    }
    if(flag == false)
        cout<<"NO";
    else
        cout<<"YES";
    return 0;
}