oj.uz

Submission #706367

# Submission time Handle Problem Language Result Execution time Memory
706367 2023-03-06T10:45:25 Z bebra Bulldozer (JOI17_bulldozer) C++17
20 / 100
 2000 ms 656 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;

#define dbg(x) cerr << #x << ": " << x << endl;


struct Point {
    ll x;
    ll y;
    ll cost;

    Point(ll _x = 0, ll _y = 0, ll _cost = 0) : x(_x), y(_y), cost(_cost) {}
};


struct Vec {
    ll x;
    ll y;

    Vec(ll _x = 0, ll _y = 0) : x(_x), y(_y) {}

    Vec(const Point& p1, const Point& p2) {
        x = p2.x - p1.x;
        y = p2.y - p1.y;
    }

    ll operator*(const Vec& other) const {
        return x * other.x + y * other.y;
    }

    ll operator^(const Vec& other) const {
        return x * other.y - other.x * y;
    }
};


struct Line {
    ll a;
    ll b;
    ll c;

    Line(ll _a = 0, ll _b = 0, ll _c = 0) : a(_a), b(_b), c(_c) {}

    Line(const Point& p1, const Point& p2) {
        a = p2.y - p1.y;
        b = p1.x - p2.x;
        c = p2.x * p1.y - p1.x * p2.y;
    }

    Line(const Line& line, const Point& p) {
        a = line.a;
        b = line.b;
        c = -p.x * a - p.y * b;
    }

    Line get_orthogonal() const {
        return {-b, a, c};
    }

    ll get(const Point& p) {
        return a * p.x + b * p.y + c;
    }
};


// 1) maintain points lying on the same line (can be done by normalizing line parameters)
// 2) maintain classes of parallel lines (can be done by normalizing line parameters)
// 3) no sense to run max subarray problem more then once on the same class of parallel lines
// 4) no more than n^2 classes of parallel lines
// 5) we treat each parallel line (or point) as array element


int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int n;
    cin >> n;

    ll ans = 0;

    vector<Point> points(n);
    for (auto& [x, y, cost] : points) {
        cin >> x >> y >> cost;
        ans = max(ans, cost);
    }

    for (int i = 0; i < n; ++i) {
        for (int j = i + 1; j < n; ++j) {
            Line line(points[i], points[j]);
            ll c = max({0LL, points[i].cost + points[j].cost, points[i].cost, points[j].cost});
            vector<vector<Point>> a(2);
            ans = max(ans, c);
            for (const auto& p : points) {
                if (line.get(p) > 0) {
                    a[0].push_back(p);
                } else if (line.get(p) < 0) {
                    a[1].push_back(p);
                }
            }
            vector<ll> max_pref(2);
            for (int t = 0; t <= 1; ++t) {
                sort(a[t].begin(), a[t].end(), [&](const auto& p1, const auto& p2) {
                    return abs(line.get(p1)) < abs(line.get(p2));
                });
                ll pref = c;
                ll min_pref = min(pref, 0LL);
                for (const auto& p : a[t]) {
                    pref += p.cost;
                    min_pref = min(min_pref, pref);
                    max_pref[t] = max(max_pref[t], pref);
                    ans = max(ans, pref - min_pref);
                }
            }
            ans = max(ans, max_pref[0] + max_pref[1] - c * 2 + points[i].cost + points[j].cost);
        }
    }

    cout << ans << '\n';

    return 0;
}

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 212 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 28 ms 316 KB Output is correct
2 Correct 26 ms 212 KB Output is correct
3 Correct 26 ms 212 KB Output is correct
4 Correct 26 ms 328 KB Output is correct
5 Correct 27 ms 316 KB Output is correct
6 Correct 26 ms 320 KB Output is correct
7 Correct 28 ms 212 KB Output is correct
8 Correct 27 ms 328 KB Output is correct
9 Correct 26 ms 332 KB Output is correct
10 Correct 26 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 0 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 0 ms 320 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 1 ms 212 KB Output is correct
19 Correct 0 ms 212 KB Output is correct
20 Correct 1 ms 212 KB Output is correct
21 Correct 25 ms 212 KB Output is correct
22 Correct 31 ms 332 KB Output is correct
23 Correct 25 ms 212 KB Output is correct
24 Correct 25 ms 332 KB Output is correct
25 Correct 25 ms 336 KB Output is correct
26 Correct 25 ms 212 KB Output is correct
27 Correct 24 ms 340 KB Output is correct
28 Correct 28 ms 324 KB Output is correct
29 Correct 26 ms 212 KB Output is correct
30 Correct 26 ms 340 KB Output is correct
31 Correct 25 ms 212 KB Output is correct
32 Correct 25 ms 212 KB Output is correct

Subtask #3
0 / 35.0

# Verdict Execution time Memory Grader output
1 Correct 28 ms 316 KB Output is correct
2 Correct 26 ms 212 KB Output is correct
3 Correct 26 ms 212 KB Output is correct
4 Correct 26 ms 328 KB Output is correct
5 Correct 27 ms 316 KB Output is correct
6 Correct 26 ms 320 KB Output is correct
7 Correct 28 ms 212 KB Output is correct
8 Correct 27 ms 328 KB Output is correct
9 Correct 26 ms 332 KB Output is correct
10 Correct 26 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 0 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 0 ms 320 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 1 ms 212 KB Output is correct
19 Correct 0 ms 212 KB Output is correct
20 Correct 1 ms 212 KB Output is correct
21 Correct 25 ms 212 KB Output is correct
22 Correct 31 ms 332 KB Output is correct
23 Correct 25 ms 212 KB Output is correct
24 Correct 25 ms 332 KB Output is correct
25 Correct 25 ms 336 KB Output is correct
26 Correct 25 ms 212 KB Output is correct
27 Correct 24 ms 340 KB Output is correct
28 Correct 28 ms 324 KB Output is correct
29 Correct 26 ms 212 KB Output is correct
30 Correct 26 ms 340 KB Output is correct
31 Correct 25 ms 212 KB Output is correct
32 Correct 25 ms 212 KB Output is correct
33 Execution timed out 2058 ms 656 KB Time limit exceeded
34 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 28 ms 316 KB Output is correct
2 Correct 26 ms 212 KB Output is correct
3 Correct 26 ms 212 KB Output is correct
4 Correct 26 ms 328 KB Output is correct
5 Correct 27 ms 316 KB Output is correct
6 Correct 26 ms 320 KB Output is correct
7 Correct 28 ms 212 KB Output is correct
8 Correct 27 ms 328 KB Output is correct
9 Correct 26 ms 332 KB Output is correct
10 Correct 26 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 0 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 0 ms 320 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 1 ms 212 KB Output is correct
19 Correct 0 ms 212 KB Output is correct
20 Correct 1 ms 212 KB Output is correct
21 Correct 25 ms 212 KB Output is correct
22 Correct 31 ms 332 KB Output is correct
23 Correct 25 ms 212 KB Output is correct
24 Correct 25 ms 332 KB Output is correct
25 Correct 25 ms 336 KB Output is correct
26 Correct 25 ms 212 KB Output is correct
27 Correct 24 ms 340 KB Output is correct
28 Correct 28 ms 324 KB Output is correct
29 Correct 26 ms 212 KB Output is correct
30 Correct 26 ms 340 KB Output is correct
31 Correct 25 ms 212 KB Output is correct
32 Correct 25 ms 212 KB Output is correct
33 Execution timed out 2058 ms 656 KB Time limit exceeded
34 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 212 KB Output isn't correct
2 Halted 0 ms 0 KB -