#include <iostream>
#include <iomanip>
#include <sstream>
#include <vector>
#include <string>
#include <set>
#include <unordered_set>
#include <map>
#include <unordered_map>
#include <stack>
#include <queue>
#include <deque>
#include <algorithm>
#include <functional>
#include <iterator>
#include <limits>
#include <numeric>
#include <utility>
#include <cmath>
#include <cassert>
#include <cstdio>

using namespace std; using namespace placeholders;

using LL = long long;
using ULL = unsigned long long;
using VI = vector< int >;
using VVI = vector< vector< int > >;
using VS = vector< string >;
using SS = stringstream;
using PII = pair< int, int >;
using VPII = vector< pair< int, int > >;
template < typename T = int > using VT = vector< T >;
template < typename T = int > using VVT = vector< vector< T > >;
template < typename T = int > using LIM = numeric_limits< T >;

template < typename T > inline istream& operator>>( istream &s, vector< T > &v ){ for ( T &t : v ) { s >> t; } return s; }
template < typename T > inline ostream& operator<<( ostream &s, const vector< T > &v ){ for ( int i = 0; i < int( v.size() ); ++i ){ s << ( " " + !i ) << v[i]; } return s; }
template < typename T > inline T fromString( const string &s ) { T res; istringstream iss( s ); iss >> res; return res; };
template < typename T > inline string toString( const T &a ) { ostringstream oss; oss << a; return oss.str(); };

#define REP2( i, n ) REP3( i, 0, n )
#define REP3( i, m, n ) for ( int i = ( int )( m ); i < ( int )( n ); ++i )
#define GET_REP( a, b, c, F, ... ) F
#define REP( ... ) GET_REP( __VA_ARGS__, REP3, REP2 )( __VA_ARGS__ )
#define FOR( e, c ) for ( auto &e : c )
#define ALL( c ) ( c ).begin(), ( c ).end()
#define AALL( a, t ) ( t* )a, ( t* )a + sizeof( a ) / sizeof( t )
#define DRANGE( c, p ) ( c ).begin(), ( c ).begin() + ( p ), ( c ).end()

#define SZ( v ) ( (int)( v ).size() )
#define PB push_back
#define EM emplace
#define EB emplace_back
#define BI back_inserter

#define EXIST( c, e ) ( ( c ).find( e ) != ( c ).end() )

#define MP make_pair
#define fst first
#define snd second

#define DUMP( x ) cerr << #x << " = " << ( x ) << endl

#include <complex>
using Point =  complex< double >;
constexpr double EPS = 1e-8;
constexpr double PI = acos( -1 );
constexpr Point O( 0, 0 );

// 入力ストリームから実数二つをとって Point へ
istream& operator>> ( istream &s, Point &a )
{
	double r, i;
	s >> r >> i;
	a = Point( r, i );
	return s;
}

// 内積（ドット積）
double dot( const Point &a, const Point &b )
{
	return a.real() * b.real() + a.imag() * b.imag();
}

// 外積（クロス積）
double cross( const Point &a, const Point &b )
{
	return a.real() * b.imag() - a.imag() * b.real();
}

// CCW 関数　a -> b -> c と進むとき、反時計回りなら 1, 直進なら 0, 時計回りなら -1
// include : dot, cross
// -1, 1 := 外積の符号
//  2 := c-a-b で一直線
// -2 := a-b-c で一直線
//  0 := a-c-b で一直線
int ccw( const Point &a, const Point &b, const Point &c )
{
	if ( cross( b - a, c - a ) < -EPS )
	{
		return -1;
	}
	if ( EPS < cross( b - a, c - a ) )
	{
		return 1;
	}
	if ( dot( b - a, c - a ) < -EPS )
	{
		return 2;
	}
	if ( dot( b - a, b - a ) < dot( c - a, c - a ) )
	{
		return -2;
	}	
	return 0;
}

int main()
{
	cin.tie( 0 );
	ios::sync_with_stdio( false );

	VT< Point > ps( 5 );
	cin >> ps;

	VI ord( 5 );
	iota( ALL( ord ), 0 );

	do
	{
		int cnt = 0;
		REP( i, 5 )
		{
			int tmp = 0;
			REP( j, 5 )
			{
				tmp += ccw( ps[ ord[i] ], ps[ ord[ ( i + 1 ) % 5 ] ], ps[j] ) == 1;
			}
			cnt += tmp == 1;
		}
		if ( cnt == 5 )
		{
			cout << "YES" << endl;
			return 0;
		}
	}
	while ( next_permutation( ALL( ord ) ) );

	cout << "NO" << endl;

	return 0;
}