#ifdef NACHIA
#define _GLIBCXX_DEBUG
#else
#define NDEBUG
#endif
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using i64 = long long;
using u64 = unsigned long long;
#define rep(i,n) for(int i=0; i<int(n); i++)
const i64 INF = 1001001001001001001;
template<typename A> void chmin(A& l, const A& r){ if(r < l) l = r; }
template<typename A> void chmax(A& l, const A& r){ if(l < r) l = r; }
using namespace std;
#include <atcoder/modint>
using Modint = atcoder::static_modint<998244353>;

void testcase(){
    i64 a[3], b[3], c[3] = {};
    i64 X[4][2] = {};
    rep(i,4) rep(j,2) cin >> X[i][j];
    rep(i,3) a[i] = X[i][0] - X[3][0];
    rep(i,3) b[i] = X[i][1] - X[3][1];
    rep(i,3) c[i] = a[i] * a[i] + b[i] * b[i];
    i64 det = 0;
    rep(i,3){
        det += a[(i+0)%3] * b[(i+1)%3] * c[(i+2)%3];
        det -= a[(i+0)%3] * b[(i+2)%3] * c[(i+1)%3];
    }
    if(a[0] * b[1] - a[1] * b[0] == 0) det = 1;
    cout << (det == 0 ? "YES\n" : "NO\n");
}

int main(){
    ios::sync_with_stdio(false); cin.tie(nullptr);
    testcase();
    return 0;
}