Submission #465819

# Submission time Handle Problem Language Result Execution time Memory
465819 2021-08-16T19:23:12 Z alexxela12345 Fountain Parks (IOI21_parks) C++17
5 / 100
3130 ms 145936 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;
  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]++;
}

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;
  }
  vector<vector<int>> g(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]);
      }
    }
  }
  vector<int> used(n);
  function<void(int)> dfs;
  dfs = [&](int v) {
    used[v] = 1;
    for (int u : g[v]) {
      if (!used[u]) {
        dfs(u);
      }
    }
  };
  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});
      }
    }
    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);
  assert(*min_element(used.begin(), used.end()) == 1);

  build(u, v, a, b);
  return 1;
}
# Verdict Execution time Memory 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 1 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 868 ms 49460 KB Output is correct
10 Correct 45 ms 4944 KB Output is correct
11 Correct 300 ms 25976 KB Output is correct
12 Correct 67 ms 7320 KB Output is correct
13 Correct 100 ms 16316 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 892 KB Output is correct
16 Correct 940 ms 46932 KB Output is correct
# Verdict Execution time Memory 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 1 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 868 ms 49460 KB Output is correct
10 Correct 45 ms 4944 KB Output is correct
11 Correct 300 ms 25976 KB Output is correct
12 Correct 67 ms 7320 KB Output is correct
13 Correct 100 ms 16316 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 892 KB Output is correct
16 Correct 940 ms 46932 KB Output is correct
17 Correct 1 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 1 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 2439 ms 92020 KB Output is correct
24 Correct 1 ms 204 KB Output is correct
25 Correct 6 ms 716 KB Output is correct
26 Correct 7 ms 1148 KB Output is correct
27 Correct 10 ms 1468 KB Output is correct
28 Correct 784 ms 35652 KB Output is correct
29 Correct 1329 ms 54396 KB Output is correct
30 Correct 1906 ms 69988 KB Output is correct
31 Correct 2483 ms 91460 KB Output is correct
32 Correct 0 ms 204 KB Output is correct
33 Correct 1 ms 204 KB Output is correct
34 Correct 1 ms 232 KB Output is correct
35 Correct 0 ms 204 KB Output is correct
36 Correct 0 ms 204 KB Output is correct
37 Correct 1 ms 204 KB Output is correct
38 Correct 0 ms 204 KB Output is correct
39 Correct 1 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 5 ms 844 KB Output is correct
44 Correct 6 ms 1100 KB Output is correct
45 Runtime error 3065 ms 73484 KB Execution killed with signal 6
46 Halted 0 ms 0 KB -
# Verdict Execution time Memory 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 1 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 868 ms 49460 KB Output is correct
10 Correct 45 ms 4944 KB Output is correct
11 Correct 300 ms 25976 KB Output is correct
12 Correct 67 ms 7320 KB Output is correct
13 Correct 100 ms 16316 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 892 KB Output is correct
16 Correct 940 ms 46932 KB Output is correct
17 Correct 1 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 1 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 2439 ms 92020 KB Output is correct
24 Correct 1 ms 204 KB Output is correct
25 Correct 6 ms 716 KB Output is correct
26 Correct 7 ms 1148 KB Output is correct
27 Correct 10 ms 1468 KB Output is correct
28 Correct 784 ms 35652 KB Output is correct
29 Correct 1329 ms 54396 KB Output is correct
30 Correct 1906 ms 69988 KB Output is correct
31 Correct 2483 ms 91460 KB Output is correct
32 Correct 0 ms 204 KB Output is correct
33 Correct 1 ms 204 KB Output is correct
34 Correct 1 ms 232 KB Output is correct
35 Correct 0 ms 204 KB Output is correct
36 Correct 0 ms 204 KB Output is correct
37 Correct 1 ms 204 KB Output is correct
38 Correct 0 ms 204 KB Output is correct
39 Correct 1 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 5 ms 844 KB Output is correct
44 Correct 6 ms 1100 KB Output is correct
45 Runtime error 3065 ms 73484 KB Execution killed with signal 6
46 Halted 0 ms 0 KB -
# Verdict Execution time Memory 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 1 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 868 ms 49460 KB Output is correct
10 Correct 45 ms 4944 KB Output is correct
11 Correct 300 ms 25976 KB Output is correct
12 Correct 67 ms 7320 KB Output is correct
13 Correct 100 ms 16316 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 892 KB Output is correct
16 Correct 940 ms 46932 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 Runtime error 3130 ms 145332 KB Execution killed with signal 6
21 Halted 0 ms 0 KB -
# Verdict Execution time Memory 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 1 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 868 ms 49460 KB Output is correct
10 Correct 45 ms 4944 KB Output is correct
11 Correct 300 ms 25976 KB Output is correct
12 Correct 67 ms 7320 KB Output is correct
13 Correct 100 ms 16316 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 892 KB Output is correct
16 Correct 940 ms 46932 KB Output is correct
17 Correct 2067 ms 99732 KB Output is correct
18 Correct 2061 ms 103216 KB Output is correct
19 Runtime error 3120 ms 145936 KB Execution killed with signal 6
20 Halted 0 ms 0 KB -
# Verdict Execution time Memory 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 1 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 868 ms 49460 KB Output is correct
10 Correct 45 ms 4944 KB Output is correct
11 Correct 300 ms 25976 KB Output is correct
12 Correct 67 ms 7320 KB Output is correct
13 Correct 100 ms 16316 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 892 KB Output is correct
16 Correct 940 ms 46932 KB Output is correct
17 Correct 1 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 1 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 2439 ms 92020 KB Output is correct
24 Correct 1 ms 204 KB Output is correct
25 Correct 6 ms 716 KB Output is correct
26 Correct 7 ms 1148 KB Output is correct
27 Correct 10 ms 1468 KB Output is correct
28 Correct 784 ms 35652 KB Output is correct
29 Correct 1329 ms 54396 KB Output is correct
30 Correct 1906 ms 69988 KB Output is correct
31 Correct 2483 ms 91460 KB Output is correct
32 Correct 0 ms 204 KB Output is correct
33 Correct 1 ms 204 KB Output is correct
34 Correct 1 ms 232 KB Output is correct
35 Correct 0 ms 204 KB Output is correct
36 Correct 0 ms 204 KB Output is correct
37 Correct 1 ms 204 KB Output is correct
38 Correct 0 ms 204 KB Output is correct
39 Correct 1 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 5 ms 844 KB Output is correct
44 Correct 6 ms 1100 KB Output is correct
45 Runtime error 3065 ms 73484 KB Execution killed with signal 6
46 Halted 0 ms 0 KB -