oj.uz

Submission #955836

# Submission time Handle Problem Language Result Execution time Memory
955836 2024-03-31T14:30:34 Z chrisvilches Dragon 2 (JOI17_dragon2) C++14
60 / 100
 4000 ms 8120 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}; }
};

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;
}

map<pair<ll, ll>, int> point_idx;

int get_point_idx(const Point p) {
  const pair<ll, ll> val{p.x, p.y};
  return point_idx.at(val);
}

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()) {
      const int idx = get_point_idx(q);
      active.add(idx, 1);
    }
  }

  int total = 0;

  int j = 0;
  for (const Point p : points1) {
    while (j < (int)points2.size()) {
      const Point q = points2[j];
      const int idx = get_point_idx(q);

      if (q.to_upper().cross(p.to_upper()) < 0) break;

      if (q.above()) {
        active.add(idx, 1);
      } else {
        active.add(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;
    const Point B{Bx, By};

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

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

    for (auto [tribe_idx, points] : tribe_points) {
      sort(points.begin(), points.end(), cmp_by_b);

      for (int i = 0; i < (int)points.size(); i++) {
        const pair<ll, ll> val{points[i].x, points[i].y};
        point_idx[val] = i;
      }

      order_by_b[tribe_idx] = points;
    }

    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:143:16: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  143 |     for (auto& [_, points] : tribe_points) {
      |                ^
dragon2.cpp:151:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  151 |     for (auto [tribe_idx, points] : tribe_points) {
      |               ^

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 604 KB Output is correct
2 Correct 7 ms 820 KB Output is correct
3 Correct 47 ms 812 KB Output is correct
4 Correct 95 ms 992 KB Output is correct
5 Correct 45 ms 1364 KB Output is correct
6 Correct 3 ms 1540 KB Output is correct
7 Correct 3 ms 1112 KB Output is correct
8 Correct 3 ms 604 KB Output is correct
9 Correct 2 ms 604 KB Output is correct
10 Correct 2 ms 856 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 27 ms 3412 KB Output is correct
2 Correct 94 ms 3456 KB Output is correct
3 Correct 33 ms 3408 KB Output is correct
4 Correct 20 ms 3672 KB Output is correct
5 Correct 26 ms 6276 KB Output is correct
6 Correct 23 ms 3544 KB Output is correct
7 Correct 24 ms 3544 KB Output is correct
8 Correct 24 ms 3540 KB Output is correct
9 Correct 17 ms 3436 KB Output is correct
10 Correct 16 ms 3376 KB Output is correct

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 604 KB Output is correct
2 Correct 7 ms 820 KB Output is correct
3 Correct 47 ms 812 KB Output is correct
4 Correct 95 ms 992 KB Output is correct
5 Correct 45 ms 1364 KB Output is correct
6 Correct 3 ms 1540 KB Output is correct
7 Correct 3 ms 1112 KB Output is correct
8 Correct 3 ms 604 KB Output is correct
9 Correct 2 ms 604 KB Output is correct
10 Correct 2 ms 856 KB Output is correct
11 Correct 27 ms 3412 KB Output is correct
12 Correct 94 ms 3456 KB Output is correct
13 Correct 33 ms 3408 KB Output is correct
14 Correct 20 ms 3672 KB Output is correct
15 Correct 26 ms 6276 KB Output is correct
16 Correct 23 ms 3544 KB Output is correct
17 Correct 24 ms 3544 KB Output is correct
18 Correct 24 ms 3540 KB Output is correct
19 Correct 17 ms 3436 KB Output is correct
20 Correct 16 ms 3376 KB Output is correct
21 Correct 27 ms 3540 KB Output is correct
22 Correct 96 ms 3448 KB Output is correct
23 Correct 716 ms 3680 KB Output is correct
24 Correct 1268 ms 3924 KB Output is correct
25 Correct 148 ms 5204 KB Output is correct
26 Correct 86 ms 8108 KB Output is correct
27 Correct 33 ms 8112 KB Output is correct
28 Correct 34 ms 8120 KB Output is correct
29 Execution timed out 4046 ms 6452 KB Time limit exceeded
30 Halted 0 ms 0 KB -