Submission #1077800

#	Time	Username	Problem	Language	Result	Execution time	Memory
1077800		danikoynov	Bulldozer (JOI17_bulldozer)	C++14	0 / 100	17 ms	600 KiB

bulldozer

    #include<bits/stdc++.h>
    #define endl '\n'
     
    using namespace std;
    typedef long long ll;
     
    struct Point
    {
        ll x, y;
     
        Point(ll _x = 0, ll _y = 0)
        {
            x = _x;
            y = _y;
        }
     
        void input()
        {
            cin >> x >> y;
        }
    };
     
    const int MAXN = 2010;
    int n;
    pair < Point, ll > spot[MAXN];
    void input()
    {
        cin >> n;
        for (int i = 1; i <= n; i ++)
        {
            spot[i].first.input();
            cin >> spot[i].second;
        }
    }
     
    ll signed_area(Point A, Point B, Point C) /// returns signed area * 2
    {
        ll area = (B.x - A.x) * (A.y + B.y) +
                    (C.x - B.x) * (B.y + C.y) +
                        (A.x - C.x) * (C.y + A.y);
        return area;
    }
     
    int orient(Point A, Point B, Point C)
    {
     
        ll area = signed_area(A, B, C);
     
        if (area > 0)
            return 1;
        if (area < 0)
            return -1;
        assert(area != 0);
        return 0;
    }
     
    void simulate()
    {
        ll result = 0;
        for (int i = 1; i <= n; i ++)
            for (int j = i + 1; j <= n; j ++)
            {
                vector < pair < ll, ll > > pos, neg;
                for (int k = 1; k <= n; k ++)
                {
                    if (k == i || k == j)
                        continue;
                    ll area = signed_area(spot[i].first, 
                                            spot[j].first, 
                                            spot[k].first);
                    /**if (i == 3 && j == 4)
                    {
                        cout << "pair with " << k << " area " << area << " value " << spot[k].second << endl;
                    }*/
                    assert(area != 0);
                    if (area > 0)
                        pos.push_back({area, spot[k].second});
                    else
                        neg.push_back({-area, spot[k].second});
                    
                }
     
                sort(pos.begin(), pos.end());
                sort(neg.begin(), neg.end());
     
                ll best = 0, sum = 0;
                ll ls = -1;
                for (pair < ll, ll > cur : pos)
                {
                    sum += cur.second;
                    assert(cur.first != ls);
                    ls = cur.first;
                    best = max(best, sum);
                }
                ls = -1;
                sum = 0;
                for (pair < ll, ll > cur : neg)
                {
                    sum += cur.second;
                    assert(cur.first != ls);
                    ls = cur.first;
                    best = max(best, sum);
                }

                //cout << "HERE " << best << endl;
                best = best + spot[i].second;
                best = best + spot[j].second;
                //cout << "new best " << best << endl;
                //ll mx = min(spot[i].second, spot[j].second);
                //cout << "mx " << mx << endl;
                if (spot[i].second < 0)
                    best -= spot[i].second;
                if (spot[j].second < 0)
                    best -= spot[j].second;
                //cout << "pair " << i << " " << j << " " << best << endl;
                result = max(result, best);
     
            }
     
        cout << result << endl;
    }
    void solve()
    {
        input();
        simulate();
    }
    int main()
    {
        solve();
        return 0;
    }
    /*
    3
    0 0 1
    1 0 1
    2 0 1
    */

• Subtask 1: 0 / 5
• Subtask 2: 0 / 20
• Subtask 3: 0 / 35
• Subtask 4: 0 / 20
• Subtask 5: 0 / 20