oj.uz

Submission #955837

# Submission time Handle Problem Language Result Execution time Memory
955837 2024-03-31T14:37:30 Z chrisvilches Dragon 2 (JOI17_dragon2) C++14
60 / 100
 4000 ms 6952 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;
  int idx;
  Point operator-(const Point p) const { return {x - p.x, y - p.y, idx}; }
  Point operator+(const Point p) const { return {x + p.x, y + p.y, idx}; }
  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 {
    // TODO: Improve this
    const Point B{Bx, By, -1};
    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, idx}; }
};

template <class T, unsigned int N>
struct BIT {
  void clear(const int n) { fill(bit, bit + n, 0); }

  T sum(int l, int r) { return sum(r) - sum(l - 1); }

  void add(unsigned int idx, const T delta) {
    for (; idx < N; idx = idx | (idx + 1)) bit[idx] += delta;
  }

 private:
  T bit[N];

  T sum(int r) {
    T ret = 0;
    for (; r >= 0; r = (r & (r + 1)) - 1) ret += bit[r];
    return ret;
  }
};

ostream& operator<<(ostream& os, const Point& p) {
  return os << "(" << p.x << ", " << p.y << ")";
}

map<int, vector<Point>> order_by_b;

bool cmp_by_b(Point p, Point q) {
  p.x -= Bx;
  q.x -= Bx;
  p.y -= By;
  q.y -= By;
  const bool a1 = p.above();
  const bool a2 = q.above();
  if (a1 != a2) return a1;
  return p.cross(q) > 0;
}

BIT<int, 30'001> active;

int handle_query(const vector<Point>& points1, const vector<Point>& points2,
                 const vector<Point>& ord_b, const Point B) {
  if (points1.empty() || points2.empty()) return 0;

  active.clear(points2.size());

  for (const auto q : points2) {
    if (!q.above()) {
      active.add(q.idx, 1);
    }
  }

  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()) {
        active.add(q.idx, 1);
      } else {
        active.add(q.idx, -1);
      }
      j++;
    }

    Point from_point = p;
    Point to_point = B + (p - B).negate();

    if (!p.above()) swap(from_point, to_point);

    const auto it1 = lower_bound(ord_b.begin(), ord_b.end(), from_point, cmp_by_b);
    const auto it2 = lower_bound(ord_b.begin(), ord_b.end(), to_point, cmp_by_b);

    const int from = it1 - ord_b.begin();
    const int to = it2 - ord_b.begin();

    total += active.sum(from, to - 1);
  }

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

    for (auto& [tribe_idx, points] : tribe_points) {
      sort(points.begin(), points.end(), cmp_by_b);
      for (int i = 0; i < (int)points.size(); i++) points[i].idx = i;
      order_by_b[tribe_idx] = points;
    }

    for (auto& [_, points] : tribe_points) {
      sort(points.begin(), points.end());
    }

    const Point B{Bx, By, -1};

    while (Q--) {
      int i, j;
      cin >> i >> j;

      cout << handle_query(tribe_points[i], tribe_points[j], order_by_b[j], B) << '\n';
    }
  }
}

Compilation message

dragon2.cpp: In function 'int main()':
dragon2.cpp:135:16: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  135 |     for (auto& [_, points] : tribe_points) {
      |                ^
dragon2.cpp:139:16: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  139 |     for (auto& [tribe_idx, points] : tribe_points) {
      |                ^
dragon2.cpp:145:16: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  145 |     for (auto& [_, points] : tribe_points) {
      |                ^

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 600 KB Output is correct
2 Correct 4 ms 604 KB Output is correct
3 Correct 22 ms 700 KB Output is correct
4 Correct 51 ms 860 KB Output is correct
5 Correct 35 ms 1192 KB Output is correct
6 Correct 2 ms 856 KB Output is correct
7 Correct 2 ms 1092 KB Output is correct
8 Correct 3 ms 604 KB Output is correct
9 Correct 2 ms 604 KB Output is correct
10 Correct 1 ms 604 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 1860 KB Output is correct
2 Correct 46 ms 1880 KB Output is correct
3 Correct 18 ms 2304 KB Output is correct
4 Correct 13 ms 2140 KB Output is correct
5 Correct 18 ms 4696 KB Output is correct
6 Correct 16 ms 2164 KB Output is correct
7 Correct 16 ms 2176 KB Output is correct
8 Correct 16 ms 2084 KB Output is correct
9 Correct 11 ms 1876 KB Output is correct
10 Correct 11 ms 1876 KB Output is correct

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 600 KB Output is correct
2 Correct 4 ms 604 KB Output is correct
3 Correct 22 ms 700 KB Output is correct
4 Correct 51 ms 860 KB Output is correct
5 Correct 35 ms 1192 KB Output is correct
6 Correct 2 ms 856 KB Output is correct
7 Correct 2 ms 1092 KB Output is correct
8 Correct 3 ms 604 KB Output is correct
9 Correct 2 ms 604 KB Output is correct
10 Correct 1 ms 604 KB Output is correct
11 Correct 18 ms 1860 KB Output is correct
12 Correct 46 ms 1880 KB Output is correct
13 Correct 18 ms 2304 KB Output is correct
14 Correct 13 ms 2140 KB Output is correct
15 Correct 18 ms 4696 KB Output is correct
16 Correct 16 ms 2164 KB Output is correct
17 Correct 16 ms 2176 KB Output is correct
18 Correct 16 ms 2084 KB Output is correct
19 Correct 11 ms 1876 KB Output is correct
20 Correct 11 ms 1876 KB Output is correct
21 Correct 18 ms 2088 KB Output is correct
22 Correct 47 ms 1884 KB Output is correct
23 Correct 312 ms 2712 KB Output is correct
24 Correct 464 ms 2552 KB Output is correct
25 Correct 74 ms 3740 KB Output is correct
26 Correct 63 ms 6464 KB Output is correct
27 Correct 20 ms 6324 KB Output is correct
28 Correct 20 ms 6328 KB Output is correct
29 Execution timed out 4070 ms 6952 KB Time limit exceeded
30 Halted 0 ms 0 KB -