oj.uz

Submission #955898

# Submission time Handle Problem Language Result Execution time Memory
955898 2024-03-31T16:24:14 Z chrisvilches Dragon 2 (JOI17_dragon2) C++14
60 / 100
 4000 ms 11984 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;

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>
struct BIT {
  BIT(const int n) : n(n) { bit.assign(n, 0); }
  // void clear(const int n) { memset(bit, 0, n * sizeof(T)); }

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

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

 private:
  int n;
  vector<T> bit;

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

unordered_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;
}

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;

  BIT<short> active(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;
      active.add(q.idx, q.above() ? 1 : -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);
    if (it1 == ord_b.end()) continue;
    int from = it1->idx;
    int to = it2->idx;
    if (it2 == ord_b.end()) to = ord_b.size();

    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};

    map<pair<int, int>, int> memo;

    while (Q--) {
      int i, j;
      cin >> i >> j;
      if (memo.count({i, j})) {
        cout << memo.count({i, j}) << '\n';
        continue;
      }

      const int ans = handle_query(tribe_points[i], tribe_points[j], order_by_b[j], B);
      memo[{i, j}] = ans;
      cout << ans << '\n';
    }
  }
}

Compilation message

dragon2.cpp: In function 'int main()':
dragon2.cpp:127:16: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  127 |     for (auto& [_, points] : tribe_points) {
      |                ^
dragon2.cpp:131:16: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  131 |     for (auto& [tribe_idx, points] : tribe_points) {
      |                ^
dragon2.cpp:137:16: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  137 |     for (auto& [_, points] : tribe_points) {
      |                ^

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 604 KB Output is correct
2 Correct 4 ms 604 KB Output is correct
3 Correct 22 ms 860 KB Output is correct
4 Correct 88 ms 7148 KB Output is correct
5 Correct 83 ms 7248 KB Output is correct
6 Correct 2 ms 860 KB Output is correct
7 Correct 3 ms 860 KB Output is correct
8 Correct 2 ms 512 KB Output is correct
9 Correct 1 ms 556 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 20 ms 2016 KB Output is correct
2 Correct 46 ms 1884 KB Output is correct
3 Correct 18 ms 2392 KB Output is correct
4 Correct 13 ms 2140 KB Output is correct
5 Correct 19 ms 4352 KB Output is correct
6 Correct 15 ms 2104 KB Output is correct
7 Correct 15 ms 2168 KB Output is correct
8 Correct 16 ms 1880 KB Output is correct
9 Correct 13 ms 1896 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 604 KB Output is correct
2 Correct 4 ms 604 KB Output is correct
3 Correct 22 ms 860 KB Output is correct
4 Correct 88 ms 7148 KB Output is correct
5 Correct 83 ms 7248 KB Output is correct
6 Correct 2 ms 860 KB Output is correct
7 Correct 3 ms 860 KB Output is correct
8 Correct 2 ms 512 KB Output is correct
9 Correct 1 ms 556 KB Output is correct
10 Correct 1 ms 604 KB Output is correct
11 Correct 20 ms 2016 KB Output is correct
12 Correct 46 ms 1884 KB Output is correct
13 Correct 18 ms 2392 KB Output is correct
14 Correct 13 ms 2140 KB Output is correct
15 Correct 19 ms 4352 KB Output is correct
16 Correct 15 ms 2104 KB Output is correct
17 Correct 15 ms 2168 KB Output is correct
18 Correct 16 ms 1880 KB Output is correct
19 Correct 13 ms 1896 KB Output is correct
20 Correct 11 ms 1876 KB Output is correct
21 Correct 18 ms 1876 KB Output is correct
22 Correct 47 ms 1908 KB Output is correct
23 Correct 295 ms 2628 KB Output is correct
24 Correct 483 ms 8812 KB Output is correct
25 Correct 117 ms 9636 KB Output is correct
26 Correct 96 ms 11984 KB Output is correct
27 Correct 21 ms 6584 KB Output is correct
28 Correct 21 ms 6836 KB Output is correct
29 Execution timed out 4066 ms 9872 KB Time limit exceeded
30 Halted 0 ms 0 KB -