Submission #567131

# Submission time Handle Problem Language Result Execution time Memory
567131 2022-05-23T08:19:29 Z 600Mihnea The Forest of Fangorn (CEOI14_fangorn) C++17
50 / 100
48 ms 468 KB
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef double ld;

struct Vector {
  ll x;
  ll y;
};

Vector operator + (Vector a, Vector b) {
  return { a.x + b.x, a.y + b.y };
}

Vector operator - (Vector a, Vector b) {
  return { a.x - b.x, a.y - b.y };
}

Vector operator * (Vector a, ll b) {
  return { a.x * b, a.y * b };
}


Vector operator * (ll b, Vector a) {
  return { a.x * b, a.y * b };
}


Vector readVector() {
  int x, y;
  cin >> x >> y;
  return { x, y };
}

const int N = 2000 + 7;
const int C = 10000 + 7;

int w, h;
int n, c;
int cnt_good[C];
Vector camps[C];
Vector trees[N];
Vector myself;


bool cmp(pair<Vector, int> a, pair<Vector, int> b) {
  return atan2((ld)a.first.y, (ld)a.first.x) < atan2((ld)b.first.y, (ld)b.first.x);
}

int get_type(Vector a) {

  if (a.x == w) return 0;
  if (a.y == h) return 1;
  if (a.x == 0) return 2;
  if (a.y == 0) return 3;
}

bool cmpOnRect(int i, int j) {
  Vector a = camps[i];
  Vector b = camps[j];

  int type_a = get_type(a);
  int type_b = get_type(b);
  if (type_a != type_b) return type_a < type_b;
  int type = type_a;

  if (type == 0) {
    return a.y < b.y;
  }
  if (type == 1) {
    return a.x > b.x;
  }
  if (type == 2) {
    return a.y > b.y;
  }
  if (type == 3) {
    return a.x < b.x;
  }
}

signed main() {
  ios::sync_with_stdio(0); cin.tie(0);

  cin >> w >> h;
  myself = readVector();

  vector<int> inds;

  cin >> c;
  for (int i = 1; i <= c; i++) {
    camps[i] = readVector();
    inds.push_back(i);
  }
  sort(inds.begin(), inds.end(), cmpOnRect);

  cin >> n;
  for (int i = 1; i <= n; i++) {
    trees[i] = readVector();
  }

  bool is = (n >= 1000);

  for (int tid = 1; tid <= n; tid++) {
    Vector origin = trees[tid];
    vector<pair<Vector, int>> events;
    for (int i = 1; i <= n; i++) {
      if (i == tid) continue;
      Vector delta = trees[i] - origin;
      events.push_back({ {-delta.x,-delta.y}, -1 });
    }
    events.push_back({ myself - origin, 0 });


    if (is) {
      continue;
    }
    auto cop_events = events;

    ld minAng = (ld)1e18;
    int start = -1;

    for (int P = 0; P < c; P++) {
      int i = inds[P];
      Vector vec = camps[i] - origin;
      ld ang = atan2(vec.y, vec.x);
      if (ang < minAng) {
        minAng = ang;
        start = P;
      }
    }

    vector<pair<Vector, int>> cps;
    for (int l = 0; l < c; l++) {
      int i = inds[(start + l) % c];
      cps.push_back({ camps[i] - origin, i });
    }

    sort(cop_events.begin(), cop_events.end(), cmp);
    vector<pair<Vector, int>> so;

    int p1 = 0, p2 = 0;
    while (p1 < (int)cps.size() && p2 < (int)cop_events.size()) {
      if (cmp(cps[p1], cop_events[p2])) {
        so.push_back(cps[p1++]);
      }
      else {
        so.push_back(cop_events[p2++]);
      }
    }
    while (p1 < (int)cps.size()) {
      so.push_back(cps[p1++]);
    }

    while (p2 < (int)cop_events.size()) {
      so.push_back(cop_events[p2++]);
    }

    events = so;
    int p0 = 0;
    while (events[p0].second != 0) p0++;

    int l = p0, r = p0, sz = (int)events.size();

    while (events[(l + sz - 1) % sz].second != -1) l = (l + sz - 1) % sz;
    while (events[(r + 1) % sz].second != -1) r = (r + 1) % sz;

    for (int j = l; j != (r + 1) % sz; j = (j + 1) % sz) {
      if (events[j].second > 0) {
        cnt_good[events[j].second]++;
      }
    }
  }
  vector<int> sol;
  for (int i = 1; i <= c; i++) {
    if (cnt_good[i] == n) {
      sol.push_back(i);
    }
  }
  cout << (int)sol.size() << "\n";
  for (auto& i : sol) {
    cout << i << " ";
  }
  cout << "\n";
}

Compilation message

fangorn.cpp: In function 'int get_type(Vector)':
fangorn.cpp:58:1: warning: control reaches end of non-void function [-Wreturn-type]
   58 | }
      | ^
fangorn.cpp: In function 'bool cmpOnRect(int, int)':
fangorn.cpp:81:1: warning: control reaches end of non-void function [-Wreturn-type]
   81 | }
      | ^
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 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 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 4 ms 212 KB Output is correct
8 Correct 3 ms 340 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 2 ms 332 KB Output is correct
3 Correct 6 ms 340 KB Output is correct
4 Correct 4 ms 340 KB Output is correct
5 Correct 4 ms 340 KB Output is correct
6 Correct 12 ms 340 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 4 ms 340 KB Output is correct
10 Correct 24 ms 340 KB Output is correct
11 Correct 20 ms 364 KB Output is correct
12 Correct 30 ms 340 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 2 ms 212 KB Output is correct
4 Incorrect 14 ms 340 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 48 ms 468 KB Output isn't correct
2 Halted 0 ms 0 KB -