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

vector<pair<int, int>> convex_hull(vector<pair<int, int>> V) {
    auto cross = [](pair<int, int> a, pair<int, int> b, pair<int, int> c) {
        b.first -= a.first;
        c.first -= a.first;
        b.second -= a.second;
        c.second -= a.second;
        return (long long)b.first * c.second - (long long)b.second * c.first;
    };
    int n = (int)V.size();
    sort(V.begin(), V.end(), [](pair<int, int> a, pair<int, int> b) {
        return a.first != b.first ? a.first < b.first : a.second < b.second;
    });
    if (n == 1)
        return V;
    int k = 0;
    vector<pair<int, int>> ret(n * 2);
    for (int i = 0; i < n; i++) {
        while (k > 1 && cross(ret[k - 1], V[i], ret[k - 2]) >= 0)
            k--;
        ret[k++] = V[i];
    }
    for (int i = n - 2, t = k; i >= 0; i--) {
        while (k > t && cross(ret[k - 1], V[i], ret[k - 2]) >= 0)
            k--;
        ret[k++] = V[i];
    }
    ret.resize(k - 1);
    return ret;
}

int main() {
    vector<pair<int, int>> P(5);
    for (int i = 0; i < 5; i++) {
        cin >> P[i].first >> P[i].second;
    }

    bool flag = false;
    vector<int> perm(5);
    iota(perm.begin(), perm.end(), 0);
    do {
        flag |= convex_hull(P).size() == 5;
    } while (next_permutation(perm.begin(), perm.end()));

    cout << (flag ? "YES" : "NO") << endl;
}