oj.uz

Submission #955966

# Submission time Handle Problem Language Result Execution time Memory
955966 2024-03-31T18:14:08 Z chrisvilches Dragon 2 (JOI17_dragon2) C++14
100 / 100
 3091 ms 4792 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = int;

ll Bx, By;

struct Point {
  ll x, y;
  int idx;
  inline Point operator-(const Point p) const { return {x - p.x, y - p.y, idx}; }
  inline Point operator+(const Point p) const { return {x + p.x, y + p.y, idx}; }
  inline long long cross(const Point p) const {
    return x * (long long)p.y - y * (long long)p.x;
  }
  inline bool operator<(const Point p) const {
    return to_upper().cross(p.to_upper()) > 0;
  }
  inline Point to_upper() const { return above() ? *this : negate(); }
  inline bool above() const {
    // TODO: Improve this
    const Point B{Bx, By, idx};
    return B.cross(*this) > 0;
  }
  inline Point negate() const { return {-x, -y, idx}; }
};

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

short bit[30'001];
int bit_n = 30'001;

void clear(const int n) { memset(bit, 0, sizeof(short) * n); }

// TODO: Return should be int, not short.
int sum_single(int r) {
  int ret = 0;
  for (; r >= 0; r = (r & (r + 1)) - 1) ret += bit[r];
  return ret;
}

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

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

unordered_map<int, vector<Point>> order_by_b;

bool cmp_by_b(const Point& p, const Point& q) {
  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_n = (int)points2.size();
  clear(points2.size());

  for (const auto& q : points2) {
    if (!q.above()) {
      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;
      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);

    // total += 1;
    // continue;

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

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

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

  return total;
}

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

  int t = 0;
  while (cin >> N >> M) {
    cerr << "--- " << (t++) << endl;
    vector<vector<Point>> tribe_points(M + 1);
    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;
    }

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

    for (int m = 0; m <= M; m++) {
      auto& points = tribe_points[m];

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

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

    const Point origin{0, 0, -1};

    int fast_queries = 50'000;
    const int big_query = N / 2;  // sqrt(N);

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

      if ((int)tribe_points[j].size() > big_query) {
        // cerr << tribe_points[j].size() << " > " << big_query << endl;
        const int ans =
            handle_query(tribe_points.at(i), tribe_points.at(j), order_by_b.at(j), B);
        cout << ans << '\n';
      } else {
        int total = 0;
        for (const Point& p : tribe_points[i]) {
          for (const Point& q : tribe_points[j]) {
            if (orientation(origin, B, p) == 1) {
              if (orientation(B, p, q) == 1 && orientation(p, origin, q) == 1) total++;
            } else {
              if (orientation(origin, p, q) == 1 && orientation(p, B, q) == 1) total++;
            }
          }
        }
        cout << total << '\n';
      }
    }
  }
}

Compilation message

dragon2.cpp: In function 'int main()':
dragon2.cpp:154:9: warning: unused variable 'fast_queries' [-Wunused-variable]
  154 |     int fast_queries = 50'000;
      |         ^~~~~~~~~~~~

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 344 KB Output is correct
2 Correct 14 ms 344 KB Output is correct
3 Correct 22 ms 348 KB Output is correct
4 Correct 27 ms 604 KB Output is correct
5 Correct 21 ms 860 KB Output is correct
6 Correct 2 ms 860 KB Output is correct
7 Correct 2 ms 860 KB Output is correct
8 Correct 2 ms 348 KB Output is correct
9 Correct 7 ms 548 KB Output is correct
10 Correct 8 ms 552 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 651 ms 1300 KB Output is correct
2 Correct 1256 ms 1280 KB Output is correct
3 Correct 38 ms 1368 KB Output is correct
4 Correct 11 ms 1368 KB Output is correct
5 Correct 14 ms 4020 KB Output is correct
6 Correct 551 ms 1244 KB Output is correct
7 Correct 528 ms 1240 KB Output is correct
8 Correct 16 ms 1244 KB Output is correct
9 Correct 636 ms 1284 KB Output is correct
10 Correct 752 ms 1284 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 344 KB Output is correct
2 Correct 14 ms 344 KB Output is correct
3 Correct 22 ms 348 KB Output is correct
4 Correct 27 ms 604 KB Output is correct
5 Correct 21 ms 860 KB Output is correct
6 Correct 2 ms 860 KB Output is correct
7 Correct 2 ms 860 KB Output is correct
8 Correct 2 ms 348 KB Output is correct
9 Correct 7 ms 548 KB Output is correct
10 Correct 8 ms 552 KB Output is correct
11 Correct 651 ms 1300 KB Output is correct
12 Correct 1256 ms 1280 KB Output is correct
13 Correct 38 ms 1368 KB Output is correct
14 Correct 11 ms 1368 KB Output is correct
15 Correct 14 ms 4020 KB Output is correct
16 Correct 551 ms 1244 KB Output is correct
17 Correct 528 ms 1240 KB Output is correct
18 Correct 16 ms 1244 KB Output is correct
19 Correct 636 ms 1284 KB Output is correct
20 Correct 752 ms 1284 KB Output is correct
21 Correct 646 ms 1304 KB Output is correct
22 Correct 1269 ms 1280 KB Output is correct
23 Correct 1315 ms 1524 KB Output is correct
24 Correct 455 ms 1760 KB Output is correct
25 Correct 43 ms 2376 KB Output is correct
26 Correct 35 ms 4276 KB Output is correct
27 Correct 15 ms 4792 KB Output is correct
28 Correct 17 ms 4792 KB Output is correct
29 Correct 3091 ms 4588 KB Output is correct
30 Correct 72 ms 4224 KB Output is correct
31 Correct 41 ms 4024 KB Output is correct
32 Correct 48 ms 4268 KB Output is correct
33 Correct 441 ms 4448 KB Output is correct
34 Correct 34 ms 4272 KB Output is correct
35 Correct 32 ms 4280 KB Output is correct
36 Correct 34 ms 4280 KB Output is correct
37 Correct 36 ms 4276 KB Output is correct
38 Correct 700 ms 4336 KB Output is correct
39 Correct 584 ms 4104 KB Output is correct
40 Correct 459 ms 4192 KB Output is correct
41 Correct 1696 ms 4564 KB Output is correct
42 Correct 1096 ms 4464 KB Output is correct
43 Correct 947 ms 4316 KB Output is correct
44 Correct 1291 ms 2728 KB Output is correct
45 Correct 657 ms 2724 KB Output is correct
46 Correct 402 ms 2740 KB Output is correct
47 Correct 1601 ms 2748 KB Output is correct
48 Correct 601 ms 2732 KB Output is correct
49 Correct 294 ms 2996 KB Output is correct