Submission #658762

# Submission time Handle Problem Language Result Execution time Memory
658762 2022-11-14T20:38:58 Z 600Mihnea Circle selection (APIO18_circle_selection) C++17
15 / 100
2415 ms 54468 KB
bool home = 0;

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int N = (int) 3e5 + 7;
const int INF = (int) 1e9 + 7;
int n;

struct Circle {
  int x;
  int y;
  int r;
};

bool doIntersect(Circle a, Circle b) {
  /// dist <= a.r + b.r
  /// dist ^  2 <= (a.r + b.r) ^ 2
  return 1LL * (a.x - b.x) * (a.x - b.x) + 1LL * (a.y - b.y) * (a.y - b.y) <= 1LL * (a.r + b.r) * (a.r + b.r);
}


Circle circles[N];
int ret[N];

map<pair<int, int>, vector<int>> guysAtPosition;


bool cmp(int i, int j) {
  if (circles[i].r == circles[j].r) {
    return i < j;
  } else {
    return circles[i].r > circles[j].r;
  }
}
set<int, decltype(cmp)*> s(cmp);

int r_divide_glob;

void place(int r_divide, set<int, decltype(cmp)*>& s) {
  r_divide_glob = r_divide;
  guysAtPosition.clear();
  for (auto &i : s) {
    guysAtPosition[{circles[i].x / r_divide, circles[i].y / r_divide}].push_back(i);
  }
}

void elim(int i, set<int, decltype(cmp)*>& s) {
  int x = circles[i].x / r_divide_glob, y = circles[i].y / r_divide_glob;
  for (int x2 = x - 2; x2 <= x + 2; x2++) {
    for (int y2 = y - 2; y2 <= y + 2; y2++) {
      pair<int, int> it = {x2, y2};
      if (!guysAtPosition.count(it)) {
        continue;
      }
      for (auto &j : guysAtPosition[it]) {
        if (doIntersect(circles[i], circles[j])) {
          ret[j] = i;
          s.erase(j);
        }
      }

    }
  }
}

int main() {
  if (home == 0) {
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  } else {
    freopen ("input.txt", "r", stdin);
  }

  cin >> n;
  for (int i = 1; i <= n; i++) {
    cin >> circles[i].x >> circles[i].y >> circles[i].r;
    circles[i].x += INF;
    circles[i].y += INF;
  }

  for (int i = 1; i <= n; i++) {
    s.insert(i);
  }
  int max_radius = circles[1].r;
  for (int i = 2; i <= n; i++) {
    max_radius = max(max_radius, circles[i].r);
  }
  place(max_radius, s);
  while (!s.empty()) {
    int i = *s.begin();
    if (circles[i].r <= max_radius / 2) {
      max_radius = circles[i].r;
      place(max_radius, s);
    }
    elim(i, s);
  }

  for (int i = 1; i <= n; i++) {
    cout << ret[i] << " ";
  }
  cout << "\n";

  return 0;
}

Compilation message

circle_selection.cpp: In function 'int main()':
circle_selection.cpp:74:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   74 |     freopen ("input.txt", "r", stdin);
      |     ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Incorrect 1 ms 340 KB Output isn't correct
9 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 449 ms 21384 KB Output is correct
2 Incorrect 487 ms 21428 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 499 ms 18164 KB Output is correct
3 Correct 2003 ms 54064 KB Output is correct
4 Correct 2050 ms 54468 KB Output is correct
5 Correct 2116 ms 47780 KB Output is correct
6 Correct 774 ms 24148 KB Output is correct
7 Correct 300 ms 13312 KB Output is correct
8 Correct 36 ms 3420 KB Output is correct
9 Correct 2415 ms 53528 KB Output is correct
10 Correct 2025 ms 46340 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1519 ms 54184 KB Output is correct
2 Correct 1102 ms 54400 KB Output is correct
3 Incorrect 878 ms 31540 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Incorrect 1 ms 340 KB Output isn't correct
9 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Incorrect 1 ms 340 KB Output isn't correct
9 Halted 0 ms 0 KB -