#include<bits/stdc++.h>
// #include<atcoder/all>
// #include<boost/multiprecision/cpp_int.hpp>

using namespace std;
// using namespace atcoder;
// using bint = boost::multiprecision::cpp_int;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using P = pair<ll,ll>;
using vi = vector<ll>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using ve = vector<vector<int>>;
using vb = vector<bool>;
using vvb = vector<vb>;
#define rep(i,s,n) for(ll i = (ll)s;i < (ll)n;i++)
#define ALL(x) (x).begin(),(x).end()
#define sz(c) ((ll)(c).size())
#define LB(A,x) (int)(lower_bound(A.begin(),A.end(),x)-A.begin())
#define UB(A,x) (int)(upper_bound(A.begin(),A.end(),x)-A.begin())
// #define MOD 1000000007
#define MOD 998244353
template<typename T>using min_priority_queue=priority_queue<T,vector<T>,greater<T>>;
template<typename T>ostream&operator<<(ostream&os,vector<T>&v){for(int i = 0;i < v.size();i++)os<<v[i]<<(i+1!=v.size()?" ":"");return os;}
template<typename T>istream&operator>>(istream&is,vector<T>&v){for(T&in:v)is>>in;return is;}
template<typename T1,typename T2>ostream&operator<<(ostream&os,pair<T1,T2>&p){os<<p.first<<" "<<p.second;return os;}
template<typename T1,typename T2>istream&operator>>(istream&is,pair<T1,T2>&p){is>>p.first>>p.second;return is;}
template<typename T> inline bool chmax(T &a,T b){if(a < b){a = b;return true;}return false;}
template<typename T> inline bool chmin(T &a,T b){if(a > b){a = b;return true;}return false;}
// ld dist(ld x1,ld y1,ld x2, ld y2){return sqrtl((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));}

const double eps = 1e-10;
using Point = complex<ld>;
#define eq(a,b) (abs((a)-(b)) < eps)
using T = ld;
istream &operator>>(istream &is,Point &p) {
  T a, b;
  is >> a >> b;
  p = Point(a, b);
  return is;
}
ostream &operator<<(ostream &os, Point &p) {
  return os << fixed << setprecision(10) << p.real() << " " << p.imag();
}
namespace std{
  bool operator<(const Point &a,const Point &b){
    return a.real() != b.real() ? a.real() < b.real() : a.imag() < b.imag();
  }
}
ld dist(Point a,Point b){return abs(a-b);}

T det(Point a,Point b){return a.real()*b.imag()-a.imag()*b.real();}

bool is_point_on_l(Point a,Point a_,Point c){return eq(det(a-a_,c-a_),0.0);}


int main(){
  
  ios_base::sync_with_stdio(0), cin.tie(0);
  Point A[4];
  rep(i,0,4)cin >> A[i];
  vi p(4);iota(ALL(p),0);
  {
    Point a = A[p[0]];
    Point b = A[p[1]];
    Point c = A[p[2]];
    Point d = A[p[3]];
    if(is_point_on_l(a,b,c) && is_point_on_l(a,b,d)){
      cout << "NO\n";
      return 0;
    }
  }
  do{
    Point a = A[p[0]];
    Point b = A[p[1]];
    Point c = A[p[2]];
    Point d = A[p[3]];
    ld k = dist(a,c)*dist(b,d);
    ld l = dist(a,d)*dist(b,c) + dist(a,b)*dist(d,c);
    if(eq(k,l)){
      cout << "YES\n";
      return 0;
    }
  }while(next_permutation(ALL(p)));
  cout << "NO\n";
  // cout << (eq(k,l) ? "YES\n" : "NO\n");
  // cout << fixed << setprecision(10);
  // cout << k << " k\n";
  // cout << l << " l\n";
  

  return 0;
}