oj.uz

Submission #955984

# Submission time Handle Problem Language Result Execution time Memory
955984 2024-03-31T18:47:57 Z chrisvilches Dragon 2 (JOI17_dragon2) C++14
60 / 100
 4000 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 Bx * (long long)y - By * (long long)x > 0;
    // 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 < p)) 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;
 
  while (cin >> N >> M) {
    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};
 
    // TODO: Are the fenwick queries actually faster???? DO some experiments
 
    // TODO: Set this value more properly, and explain that this doesn't really help
    //       but it's something. (assuming fenwick is ACTUALLY faster)
 
    // TODO: Comment that this solution is probably not the intended one. The example
    // solution is much faster (under a second).
    // TODO: The thing is, I don't want to leave this code without the radial sweep, I
    // want to add it for the lulz.
    const int big_query = N / 2;
 
 
    while (Q--) {
      int i, j;
      cin >> i >> j;
      // cerr << tribe_points[i].size() * tribe_points[j].size() << endl;
      //const long long size = tribe_points[i].size() * tribe_points[j].size();
 
      if (true) {
        // cerr << "big" << endl;
        // 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:162:15: warning: unused variable 'big_query' [-Wunused-variable]
  162 |     const int big_query = N / 2;
      |               ^~~~~~~~~

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 344 KB Output is correct
2 Correct 4 ms 572 KB Output is correct
3 Correct 19 ms 348 KB Output is correct
4 Correct 37 ms 800 KB Output is correct
5 Correct 24 ms 1120 KB Output is correct
6 Correct 2 ms 856 KB Output is correct
7 Correct 2 ms 860 KB Output is correct
8 Correct 1 ms 348 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 1 ms 348 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 1172 KB Output is correct
2 Correct 42 ms 1232 KB Output is correct
3 Correct 17 ms 1352 KB Output is correct
4 Correct 11 ms 1372 KB Output is correct
5 Correct 13 ms 4024 KB Output is correct
6 Correct 14 ms 1340 KB Output is correct
7 Correct 14 ms 1496 KB Output is correct
8 Correct 14 ms 1244 KB Output is correct
9 Correct 10 ms 1240 KB Output is correct
10 Correct 9 ms 1124 KB Output is correct

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 344 KB Output is correct
2 Correct 4 ms 572 KB Output is correct
3 Correct 19 ms 348 KB Output is correct
4 Correct 37 ms 800 KB Output is correct
5 Correct 24 ms 1120 KB Output is correct
6 Correct 2 ms 856 KB Output is correct
7 Correct 2 ms 860 KB Output is correct
8 Correct 1 ms 348 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Correct 20 ms 1172 KB Output is correct
12 Correct 42 ms 1232 KB Output is correct
13 Correct 17 ms 1352 KB Output is correct
14 Correct 11 ms 1372 KB Output is correct
15 Correct 13 ms 4024 KB Output is correct
16 Correct 14 ms 1340 KB Output is correct
17 Correct 14 ms 1496 KB Output is correct
18 Correct 14 ms 1244 KB Output is correct
19 Correct 10 ms 1240 KB Output is correct
20 Correct 9 ms 1124 KB Output is correct
21 Correct 17 ms 1136 KB Output is correct
22 Correct 42 ms 1116 KB Output is correct
23 Correct 273 ms 1504 KB Output is correct
24 Correct 392 ms 1784 KB Output is correct
25 Correct 49 ms 2384 KB Output is correct
26 Correct 37 ms 4276 KB Output is correct
27 Correct 15 ms 4792 KB Output is correct
28 Correct 15 ms 4788 KB Output is correct
29 Execution timed out 4051 ms 4396 KB Time limit exceeded
30 Halted 0 ms 0 KB -