답안 #465832

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
465832 2021-08-16T19:41:39 Z alexxela12345 분수 공원 (IOI21_parks) C++17
5 / 100
3184 ms 91948 KB
#include "parks.h"
#include <bits/stdc++.h>

using namespace std;

random_device rddev;
mt19937 rd(rddev());

int randint(int l, int r) {
  int b = r - l + 1;
  if (b <= 0) {
    exit(228);
  }
  int a = rd() % b + b;
  a %= b;
  return a + l;
}

vector<int> pa, ra;

int get(int v) {
  if (pa[v] == v)
    return v;
  return pa[v] = get(pa[v]);
}
void merge(int a, int b) {
  a = get(a);
  b = get(b);
  assert(a != b);
  if (ra[b] > ra[a])
    swap(a, b);
  pa[b] = a;
  if (ra[a] == ra[b])
    ra[a]++;
}

vector<vector<int>> g;
vector<int> used;

void dfs(int v) {
  used[v] = 1;
  deque<int> q;
  q.push_back(v);
  while (!q.empty()) {
    int v = q.front();
    q.pop_front();
    for (int u : g[v]) {
      if (!used[u]) {
        used[u] = 1;
        q.push_back(u);
      }
    }
  }
}

int construct_roads(std::vector<int> x, std::vector<int> y) {
  if (x.size() == 1) {
    build({}, {}, {}, {});
    return 1;
  }
  map<pair<int, int>, int> byc;
  int n = x.size();
  for (int i = 0; i < n; i++) {
    byc[{x[i], y[i]}] = i;
  }
  g.clear();
  g.resize(n);
  map<pair<int, int>, int> cnt;
  pa.assign(n, 0);
  ra.assign(n, 0);
  iota(pa.begin(), pa.end(), 0);
  set<pair<int, int>> alive;

  auto add = [&](int i, int j) {
    if (i < j) {
      alive.insert({i, j});
      g[i].push_back(j);
      g[j].push_back(i);
      if (x[i] == x[j]) {
        cnt[{x[i] + 1, (y[i] + y[j]) / 2}] += 1;
        cnt[{x[i] - 1, (y[i] + y[j]) / 2}] += 1;
      } else {
        cnt[{(x[i] + x[j]) / 2, y[i] + 1}] += 1;
        cnt[{(x[i] + x[j]) / 2, y[i] - 1}] += 1;
      }
    }
  };
  for (int i = 0; i < n; i++) {
    {
      pair<int, int> pp = {x[i], y[i]};
      pp.first += 2;
      if (byc.count(pp)) {
        add(i, byc[pp]);
      }
    }
    {
      pair<int, int> pp = {x[i], y[i]};
      pp.second += 2;
      if (byc.count(pp)) {
        add(i, byc[pp]);
      }
    }
    {
      pair<int, int> pp = {x[i], y[i]};
      pp.first -= 2;
      if (byc.count(pp)) {
        add(i, byc[pp]);
      }
    }
    {
      pair<int, int> pp = {x[i], y[i]};
      pp.second -= 2;
      if (byc.count(pp)) {
        add(i, byc[pp]);
      }
    }
  }
  used.assign(n, 0);
  dfs(0);
  if (*min_element(used.begin(), used.end()) == 0) {
    return 0;
  }
  set<pair<int, int>> ones;
  for (auto &el : cnt) {
    if (el.second == 1) {
      ones.insert(el.first);
    }
  }
  vector<int> u, v, a, b;

  g.clear();
  g.resize(n);

  auto chk = [&](pair<int, int> pp) {
    cnt[pp] -= 1;
    switch (cnt[pp]) {
    case 1: {
      ones.insert(pp);
    };
    case 0: {
      ones.erase(pp);
    };
    }
  };

  auto die = [&](int i, int j) {
    if (j < i)
      swap(i, j);
    alive.erase({i, j});
    if (x[i] == x[j]) {
      pair<int, int> pp;
      pp = {x[i] + 1, (y[i] + y[j]) / 2};
      chk(pp);
      pp = {x[i] - 1, (y[i] + y[j]) / 2};
      chk(pp);
    } else {
      pair<int, int> pp;
      pp = {(x[i] + x[j]) / 2, y[i] + 1};
      chk(pp);
      pp = {(x[i] + x[j]) / 2, y[i] - 1};
      chk(pp);
    }
  };
  auto al = [&](int i, int j) {
    if (j < i)
      swap(i, j);
    return alive.count({i, j});
  };
  auto check_edge = [&](int i, int j, pair<int, int> xy) {
    if (al(i, j) && get(i) != get(j)) {
      u.push_back(i);
      v.push_back(j);
      merge(i, j);
      a.push_back(xy.first);
      b.push_back(xy.second);
      die(i, j);
    } else if (al(i, j)) {
      die(i, j);
    }
  };

  while (true) {
    while (!ones.empty()) {
      pair<int, int> xy = *ones.begin();
      ones.erase(ones.begin());
      pair<int, int> RU, RD, LD, LU;
      RU = RD = LD = LU = xy;
      RU.first++, RU.second++;
      RD.first++, RD.second--;
      LU.first--, LU.second++;
      LD.first--, LD.second--;
      size_t was = u.size();
      if (byc.count(RU) && byc.count(RD)) {
        int i = byc[RU];
        int j = byc[RD];
        check_edge(i, j, xy);
      }
      if (byc.count(RD) && byc.count(LD)) {
        int i = byc[RD];
        int j = byc[LD];
        check_edge(i, j, xy);
      }
      if (byc.count(LD) && byc.count(LU)) {
        int i = byc[LD];
        int j = byc[LU];
        check_edge(i, j, xy);
      }
      if (byc.count(LU) && byc.count(RU)) {
        int i = byc[LU];
        int j = byc[RU];
        check_edge(i, j, xy);
      }
      if (u.size() != was) {
        cnt[xy] = -100;
      }
      assert(u.size() - was <= 1);
    }
    auto alive2 = alive;
    vector<pair<int, int>> kek;
    for (auto [i, j] : alive2) {
      if (get(i) == get(j)) {
        die(i, j);
      } else {
        kek.push_back({i, j});
      }
    }
    assert(kek.size() == alive.size());
    if (ones.empty()) {
      if (alive.empty() || clock() > 3 * CLOCKS_PER_SEC)
	break;
      int ind = randint(0, kek.size() - 1);
      auto [i, j] = kek[ind];
      vector<pair<int, int>> can;
      pair<int, int> pp;
      if (x[i] == x[j]) {
	pp = {x[i] + 1, (y[i] + y[j]) / 2};
	if (cnt[pp] >= 0) {
	  can.push_back(pp);
	}
	pp = {x[i] - 1, (y[i] + y[j]) / 2};
	if (cnt[pp] >= 0) {
	  can.push_back(pp);
	}
      } else {
	pp = {(x[i] + x[j]) / 2, y[i] + 1};
	if (cnt[pp] >= 0) {
	  can.push_back(pp);
	}
	pp = {(x[i] + x[j]) / 2, y[i] - 1};
        if (cnt[pp] >= 0) {
          can.push_back(pp);
        }
      }
      if (can.empty()) {
        return 0;
      }
      pair<int, int> xy = can[randint(0, can.size() - 1)];
      u.push_back(i);
      v.push_back(j);
      merge(i, j);
      a.push_back(xy.first);
      b.push_back(xy.second);
      cnt[xy] = -100;
      die(i, j);
    }
  }

  for (int i = 0; i < (int)u.size(); i++) {
    g[u[i]].push_back(v[i]);
    g[v[i]].push_back(u[i]);
  }
  used.assign(n, 0);
  dfs(0);
  if (!(*min_element(used.begin(), used.end()) == 1)) {
    return 0;
  }

  build(u, v, a, b);
  return 1;
}
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 204 KB Output is correct
8 Correct 0 ms 204 KB Output is correct
9 Correct 848 ms 43840 KB Output is correct
10 Correct 41 ms 4548 KB Output is correct
11 Correct 274 ms 23016 KB Output is correct
12 Correct 64 ms 6712 KB Output is correct
13 Correct 97 ms 14224 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 871 ms 43796 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 204 KB Output is correct
8 Correct 0 ms 204 KB Output is correct
9 Correct 848 ms 43840 KB Output is correct
10 Correct 41 ms 4548 KB Output is correct
11 Correct 274 ms 23016 KB Output is correct
12 Correct 64 ms 6712 KB Output is correct
13 Correct 97 ms 14224 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 871 ms 43796 KB Output is correct
17 Correct 1 ms 204 KB Output is correct
18 Correct 1 ms 204 KB Output is correct
19 Correct 0 ms 204 KB Output is correct
20 Correct 1 ms 204 KB Output is correct
21 Correct 0 ms 204 KB Output is correct
22 Correct 0 ms 240 KB Output is correct
23 Correct 2466 ms 80196 KB Output is correct
24 Correct 1 ms 204 KB Output is correct
25 Correct 5 ms 744 KB Output is correct
26 Correct 7 ms 1100 KB Output is correct
27 Correct 10 ms 1504 KB Output is correct
28 Correct 780 ms 30804 KB Output is correct
29 Correct 1264 ms 47696 KB Output is correct
30 Correct 1892 ms 63580 KB Output is correct
31 Correct 2406 ms 80156 KB Output is correct
32 Correct 0 ms 204 KB Output is correct
33 Correct 0 ms 204 KB Output is correct
34 Correct 1 ms 204 KB Output is correct
35 Correct 0 ms 204 KB Output is correct
36 Correct 0 ms 204 KB Output is correct
37 Correct 0 ms 204 KB Output is correct
38 Correct 0 ms 204 KB Output is correct
39 Correct 0 ms 204 KB Output is correct
40 Correct 0 ms 204 KB Output is correct
41 Correct 0 ms 204 KB Output is correct
42 Correct 0 ms 204 KB Output is correct
43 Correct 4 ms 844 KB Output is correct
44 Correct 6 ms 1100 KB Output is correct
45 Incorrect 3090 ms 32424 KB Solution announced impossible, but it is possible.
46 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 204 KB Output is correct
8 Correct 0 ms 204 KB Output is correct
9 Correct 848 ms 43840 KB Output is correct
10 Correct 41 ms 4548 KB Output is correct
11 Correct 274 ms 23016 KB Output is correct
12 Correct 64 ms 6712 KB Output is correct
13 Correct 97 ms 14224 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 871 ms 43796 KB Output is correct
17 Correct 1 ms 204 KB Output is correct
18 Correct 1 ms 204 KB Output is correct
19 Correct 0 ms 204 KB Output is correct
20 Correct 1 ms 204 KB Output is correct
21 Correct 0 ms 204 KB Output is correct
22 Correct 0 ms 240 KB Output is correct
23 Correct 2466 ms 80196 KB Output is correct
24 Correct 1 ms 204 KB Output is correct
25 Correct 5 ms 744 KB Output is correct
26 Correct 7 ms 1100 KB Output is correct
27 Correct 10 ms 1504 KB Output is correct
28 Correct 780 ms 30804 KB Output is correct
29 Correct 1264 ms 47696 KB Output is correct
30 Correct 1892 ms 63580 KB Output is correct
31 Correct 2406 ms 80156 KB Output is correct
32 Correct 0 ms 204 KB Output is correct
33 Correct 0 ms 204 KB Output is correct
34 Correct 1 ms 204 KB Output is correct
35 Correct 0 ms 204 KB Output is correct
36 Correct 0 ms 204 KB Output is correct
37 Correct 0 ms 204 KB Output is correct
38 Correct 0 ms 204 KB Output is correct
39 Correct 0 ms 204 KB Output is correct
40 Correct 0 ms 204 KB Output is correct
41 Correct 0 ms 204 KB Output is correct
42 Correct 0 ms 204 KB Output is correct
43 Correct 4 ms 844 KB Output is correct
44 Correct 6 ms 1100 KB Output is correct
45 Incorrect 3090 ms 32424 KB Solution announced impossible, but it is possible.
46 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 204 KB Output is correct
8 Correct 0 ms 204 KB Output is correct
9 Correct 848 ms 43840 KB Output is correct
10 Correct 41 ms 4548 KB Output is correct
11 Correct 274 ms 23016 KB Output is correct
12 Correct 64 ms 6712 KB Output is correct
13 Correct 97 ms 14224 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 871 ms 43796 KB Output is correct
17 Correct 0 ms 204 KB Output is correct
18 Correct 1 ms 204 KB Output is correct
19 Correct 0 ms 204 KB Output is correct
20 Incorrect 3180 ms 63088 KB Solution announced impossible, but it is possible.
21 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 204 KB Output is correct
8 Correct 0 ms 204 KB Output is correct
9 Correct 848 ms 43840 KB Output is correct
10 Correct 41 ms 4548 KB Output is correct
11 Correct 274 ms 23016 KB Output is correct
12 Correct 64 ms 6712 KB Output is correct
13 Correct 97 ms 14224 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 871 ms 43796 KB Output is correct
17 Correct 2033 ms 87156 KB Output is correct
18 Correct 2056 ms 91948 KB Output is correct
19 Incorrect 3184 ms 63036 KB Solution announced impossible, but it is possible.
20 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 204 KB Output is correct
8 Correct 0 ms 204 KB Output is correct
9 Correct 848 ms 43840 KB Output is correct
10 Correct 41 ms 4548 KB Output is correct
11 Correct 274 ms 23016 KB Output is correct
12 Correct 64 ms 6712 KB Output is correct
13 Correct 97 ms 14224 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 871 ms 43796 KB Output is correct
17 Correct 1 ms 204 KB Output is correct
18 Correct 1 ms 204 KB Output is correct
19 Correct 0 ms 204 KB Output is correct
20 Correct 1 ms 204 KB Output is correct
21 Correct 0 ms 204 KB Output is correct
22 Correct 0 ms 240 KB Output is correct
23 Correct 2466 ms 80196 KB Output is correct
24 Correct 1 ms 204 KB Output is correct
25 Correct 5 ms 744 KB Output is correct
26 Correct 7 ms 1100 KB Output is correct
27 Correct 10 ms 1504 KB Output is correct
28 Correct 780 ms 30804 KB Output is correct
29 Correct 1264 ms 47696 KB Output is correct
30 Correct 1892 ms 63580 KB Output is correct
31 Correct 2406 ms 80156 KB Output is correct
32 Correct 0 ms 204 KB Output is correct
33 Correct 0 ms 204 KB Output is correct
34 Correct 1 ms 204 KB Output is correct
35 Correct 0 ms 204 KB Output is correct
36 Correct 0 ms 204 KB Output is correct
37 Correct 0 ms 204 KB Output is correct
38 Correct 0 ms 204 KB Output is correct
39 Correct 0 ms 204 KB Output is correct
40 Correct 0 ms 204 KB Output is correct
41 Correct 0 ms 204 KB Output is correct
42 Correct 0 ms 204 KB Output is correct
43 Correct 4 ms 844 KB Output is correct
44 Correct 6 ms 1100 KB Output is correct
45 Incorrect 3090 ms 32424 KB Solution announced impossible, but it is possible.
46 Halted 0 ms 0 KB -