oj.uz

Submission #465831

# Submission time Handle Problem Language Result Execution time Memory
465831 2021-08-16T19:40:47 Z alexxela12345 Fountain Parks (IOI21_parks) C++17
5 / 100
 3168 ms 91952 KB 
#include "parks.h"
#include <bits/stdc++.h>

using namespace std;

mt19937 rd(179);

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;
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 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 0 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 864 ms 43864 KB Output is correct
10 Correct 53 ms 4500 KB Output is correct
11 Correct 281 ms 23096 KB Output is correct
12 Correct 67 ms 6640 KB Output is correct
13 Correct 94 ms 14244 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 838 ms 43696 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 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 0 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 864 ms 43864 KB Output is correct
10 Correct 53 ms 4500 KB Output is correct
11 Correct 281 ms 23096 KB Output is correct
12 Correct 67 ms 6640 KB Output is correct
13 Correct 94 ms 14244 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 838 ms 43696 KB Output is correct
17 Correct 0 ms 204 KB Output is correct
18 Correct 0 ms 204 KB Output is correct
19 Correct 0 ms 204 KB Output is correct
20 Correct 0 ms 204 KB Output is correct
21 Correct 0 ms 204 KB Output is correct
22 Correct 0 ms 204 KB Output is correct
23 Correct 2372 ms 80160 KB Output is correct
24 Correct 1 ms 204 KB Output is correct
25 Correct 5 ms 716 KB Output is correct
26 Correct 7 ms 1100 KB Output is correct
27 Correct 10 ms 1448 KB Output is correct
28 Correct 773 ms 30748 KB Output is correct
29 Correct 1339 ms 47796 KB Output is correct
30 Correct 1854 ms 63528 KB Output is correct
31 Correct 2468 ms 80280 KB Output is correct
32 Correct 1 ms 204 KB Output is correct
33 Correct 0 ms 204 KB Output is correct
34 Correct 0 ms 204 KB Output is correct
35 Correct 1 ms 204 KB Output is correct
36 Correct 1 ms 204 KB Output is correct
37 Correct 1 ms 204 KB Output is correct
38 Correct 1 ms 204 KB Output is correct
39 Correct 1 ms 204 KB Output is correct
40 Correct 1 ms 204 KB Output is correct
41 Correct 1 ms 204 KB Output is correct
42 Correct 0 ms 204 KB Output is correct
43 Correct 4 ms 716 KB Output is correct
44 Correct 6 ms 1100 KB Output is correct
45 Incorrect 3113 ms 32584 KB Solution announced impossible, but it is possible.
46 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 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 0 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 864 ms 43864 KB Output is correct
10 Correct 53 ms 4500 KB Output is correct
11 Correct 281 ms 23096 KB Output is correct
12 Correct 67 ms 6640 KB Output is correct
13 Correct 94 ms 14244 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 838 ms 43696 KB Output is correct
17 Correct 0 ms 204 KB Output is correct
18 Correct 0 ms 204 KB Output is correct
19 Correct 0 ms 204 KB Output is correct
20 Correct 0 ms 204 KB Output is correct
21 Correct 0 ms 204 KB Output is correct
22 Correct 0 ms 204 KB Output is correct
23 Correct 2372 ms 80160 KB Output is correct
24 Correct 1 ms 204 KB Output is correct
25 Correct 5 ms 716 KB Output is correct
26 Correct 7 ms 1100 KB Output is correct
27 Correct 10 ms 1448 KB Output is correct
28 Correct 773 ms 30748 KB Output is correct
29 Correct 1339 ms 47796 KB Output is correct
30 Correct 1854 ms 63528 KB Output is correct
31 Correct 2468 ms 80280 KB Output is correct
32 Correct 1 ms 204 KB Output is correct
33 Correct 0 ms 204 KB Output is correct
34 Correct 0 ms 204 KB Output is correct
35 Correct 1 ms 204 KB Output is correct
36 Correct 1 ms 204 KB Output is correct
37 Correct 1 ms 204 KB Output is correct
38 Correct 1 ms 204 KB Output is correct
39 Correct 1 ms 204 KB Output is correct
40 Correct 1 ms 204 KB Output is correct
41 Correct 1 ms 204 KB Output is correct
42 Correct 0 ms 204 KB Output is correct
43 Correct 4 ms 716 KB Output is correct
44 Correct 6 ms 1100 KB Output is correct
45 Incorrect 3113 ms 32584 KB Solution announced impossible, but it is possible.
46 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 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 0 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 864 ms 43864 KB Output is correct
10 Correct 53 ms 4500 KB Output is correct
11 Correct 281 ms 23096 KB Output is correct
12 Correct 67 ms 6640 KB Output is correct
13 Correct 94 ms 14244 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 838 ms 43696 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 Incorrect 3168 ms 63028 KB Solution announced impossible, but it is possible.
21 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 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 0 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 864 ms 43864 KB Output is correct
10 Correct 53 ms 4500 KB Output is correct
11 Correct 281 ms 23096 KB Output is correct
12 Correct 67 ms 6640 KB Output is correct
13 Correct 94 ms 14244 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 838 ms 43696 KB Output is correct
17 Correct 2097 ms 87140 KB Output is correct
18 Correct 2024 ms 91952 KB Output is correct
19 Incorrect 3154 ms 63028 KB Solution announced impossible, but it is possible.
20 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 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 0 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 864 ms 43864 KB Output is correct
10 Correct 53 ms 4500 KB Output is correct
11 Correct 281 ms 23096 KB Output is correct
12 Correct 67 ms 6640 KB Output is correct
13 Correct 94 ms 14244 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 838 ms 43696 KB Output is correct
17 Correct 0 ms 204 KB Output is correct
18 Correct 0 ms 204 KB Output is correct
19 Correct 0 ms 204 KB Output is correct
20 Correct 0 ms 204 KB Output is correct
21 Correct 0 ms 204 KB Output is correct
22 Correct 0 ms 204 KB Output is correct
23 Correct 2372 ms 80160 KB Output is correct
24 Correct 1 ms 204 KB Output is correct
25 Correct 5 ms 716 KB Output is correct
26 Correct 7 ms 1100 KB Output is correct
27 Correct 10 ms 1448 KB Output is correct
28 Correct 773 ms 30748 KB Output is correct
29 Correct 1339 ms 47796 KB Output is correct
30 Correct 1854 ms 63528 KB Output is correct
31 Correct 2468 ms 80280 KB Output is correct
32 Correct 1 ms 204 KB Output is correct
33 Correct 0 ms 204 KB Output is correct
34 Correct 0 ms 204 KB Output is correct
35 Correct 1 ms 204 KB Output is correct
36 Correct 1 ms 204 KB Output is correct
37 Correct 1 ms 204 KB Output is correct
38 Correct 1 ms 204 KB Output is correct
39 Correct 1 ms 204 KB Output is correct
40 Correct 1 ms 204 KB Output is correct
41 Correct 1 ms 204 KB Output is correct
42 Correct 0 ms 204 KB Output is correct
43 Correct 4 ms 716 KB Output is correct
44 Correct 6 ms 1100 KB Output is correct
45 Incorrect 3113 ms 32584 KB Solution announced impossible, but it is possible.
46 Halted 0 ms 0 KB -