#include <bits/stdc++.h>
using namespace std;

int main() {
	int n, x, y, a, b, cnt = 2;
	long double m;
	cin>>n>>a>>b>>x>>y;
	
	if(x!=a){
		m = 1.0*(y-b)/(1.0*(x-a));
		// cout<<m<<endl;
	}
	else{ 
		m = (double)0x7fffffff;
	}
	bool ans = 1;
	// cout<<m<<endl;
	for(int i=2;i<n;i++){
		cin>>x>>y;
		// cout<<m<<endl;
		if(x!=a){
			// cout<<"here"<<endl;
			if(abs(m*(x-a) - 1.0*(y-b)) <= 0.0000001*abs((x-a))){
				// cout<<"here"<<endl;
				// cout<<(1.0*(y-b))/(1.0*(x-a))<<endl;
				// cout<<m*(x-a)-1.0*(y-b)<<endl;
				ans = 1;
				cnt++;
			}
		}
		else {
			// cout<<"here"<<endl;
			if(m-(double)0x7fffffff<=0.0000001){
				cnt++;
				// cout<<"here"<<endl;		
			}	
		}
	}
	if(cnt==n)cout<<"YES"<<endl;
	else cout<<"NO"<<endl;
	return 0;
}