oj.uz

Submission #955811

# Submission time Handle Problem Language Result Execution time Memory
955811 2024-03-31T12:45:02 Z chrisvilches Dragon 2 (JOI17_dragon2) C++14
15 / 100
 4000 ms 2512 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;

// TODO: New index category: point inside polygon (log N), and polygon tangent.

ll Bx, By;

struct Point {
  ll x, y;
  Point operator-(const Point p) const { return {x - p.x, y - p.y}; }
  Point operator+(const Point p) const { return {x + p.x, y + p.y}; }
  ll cross(const Point p) const { return x * p.y - y * p.x; }
  bool operator<(const Point p) const { return to_upper().cross(p.to_upper()) > 0; }
  Point to_upper() const { return above() ? *this : negate(); }
  bool above() const {
    const Point B{Bx, By};
    return B.cross(*this) > 0;
  }
  ll operator*(const Point p) const { return x * p.x + y * p.y; }
  bool deg0(const Point p) const { return cross(p) == 0 && *this * p >= 0; }
  bool deg180(const Point p) const { return cross(p) == 0 && *this * p < 0; }
  Point negate() const { return {-x, -y}; }
};
ostream& operator<<(ostream& os, const Point& p) {
  return os << "(" << p.x << ", " << p.y << ")";
}

short orientation(const Point o, const Point a, const Point b) {
  const ll cross = (a - o).cross(b - o);
  assert(cross != 0);
  return (cross > 0) - (cross < 0);
}

int handle_query(const vector<Point>& points1, const vector<Point>& points2,
                 const Point B) {
  set<Point> active;

  for (const auto q : points2) {
    if (!q.above()) {
      active.emplace(q);
    }
  }

  int total = 0;

  int j = 0;
  for (const Point p : points1) {
    while (j < (int)points2.size()) {
      const Point q = points2[j];
      if (q.to_upper().cross(p.to_upper()) < 0) {
        break;
      }
      if (q.above()) {
        assert(!active.count(q));
        active.emplace(q);
        assert(active.count(q));
      } else {
        assert(active.count(q));
        active.erase(q);
        assert(!active.count(q));
      }
      j++;
    }

    // TODO: (Brute force)
    for (const Point q : points2) {
      if (!active.count(q)) continue;
      if (p.above()) {
        if (orientation(B, p, q) > 0) total++;
      } else {
        if (orientation(p, B, q) > 0) total++;
      }
    }
  }

  return total;
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int N, M, Q;

  while (cin >> N >> M) {
    vector<Point> points;
    unordered_map<int, vector<Point>> tribe_points;
    for (int i = 0; i < N; i++) {
      Point p;
      int tribe;
      cin >> p.x >> p.y >> tribe;
      tribe_points[tribe].push_back(p);
    }

    Point A;
    cin >> A.x >> A.y;
    cin >> Bx >> By;
    cin >> Q;
    Bx -= A.x;
    By -= A.y;
    const Point B{Bx, By};

    for (auto& [_, points] : tribe_points) {
      for (auto& p : points) {
        p = p - A;
      }

      sort(points.begin(), points.end());
    }

    while (Q--) {
      int i, j;
      cin >> i >> j;
      cout << handle_query(tribe_points[i], tribe_points[j], B) << '\n';
    }
  }
}

Compilation message

dragon2.cpp: In function 'int main()':
dragon2.cpp:103:16: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  103 |     for (auto& [_, points] : tribe_points) {
      |                ^

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 90 ms 648 KB Output is correct
2 Correct 102 ms 604 KB Output is correct
3 Correct 103 ms 656 KB Output is correct
4 Correct 51 ms 1564 KB Output is correct
5 Correct 27 ms 1724 KB Output is correct
6 Correct 2 ms 600 KB Output is correct
7 Correct 2 ms 600 KB Output is correct
8 Correct 110 ms 668 KB Output is correct
9 Correct 106 ms 604 KB Output is correct
10 Correct 101 ms 604 KB Output is correct

Subtask #2
0 / 45.0

# Verdict Execution time Memory Grader output
1 Execution timed out 4029 ms 2512 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 90 ms 648 KB Output is correct
2 Correct 102 ms 604 KB Output is correct
3 Correct 103 ms 656 KB Output is correct
4 Correct 51 ms 1564 KB Output is correct
5 Correct 27 ms 1724 KB Output is correct
6 Correct 2 ms 600 KB Output is correct
7 Correct 2 ms 600 KB Output is correct
8 Correct 110 ms 668 KB Output is correct
9 Correct 106 ms 604 KB Output is correct
10 Correct 101 ms 604 KB Output is correct
11 Execution timed out 4029 ms 2512 KB Time limit exceeded
12 Halted 0 ms 0 KB -