Submission #465825

# Submission time Handle Problem Language Result Execution time Memory
465825 2021-08-16T19:29:00 Z alexxela12345 Fountain Parks (IOI21_parks) C++17
5 / 100
3127 ms 133216 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]++;
}

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

void dfs(int v) {
  used[v] = 1;
  for (int u : g[v])
    if (!used[u])
      dfs(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);
  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 0 ms 204 KB Output is correct
5 Correct 1 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 1 ms 204 KB Output is correct
9 Correct 870 ms 46692 KB Output is correct
10 Correct 41 ms 4804 KB Output is correct
11 Correct 286 ms 24708 KB Output is correct
12 Correct 67 ms 7156 KB Output is correct
13 Correct 102 ms 15220 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 906 ms 45336 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 0 ms 204 KB Output is correct
5 Correct 1 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 1 ms 204 KB Output is correct
9 Correct 870 ms 46692 KB Output is correct
10 Correct 41 ms 4804 KB Output is correct
11 Correct 286 ms 24708 KB Output is correct
12 Correct 67 ms 7156 KB Output is correct
13 Correct 102 ms 15220 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 906 ms 45336 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 2464 ms 86028 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 1228 KB Output is correct
27 Correct 10 ms 1504 KB Output is correct
28 Correct 806 ms 33072 KB Output is correct
29 Correct 1354 ms 50996 KB Output is correct
30 Correct 1861 ms 66780 KB Output is correct
31 Correct 2389 ms 85744 KB Output is correct
32 Correct 0 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 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 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 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 1032 KB Output is correct
45 Runtime error 3064 ms 69596 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 0 ms 204 KB Output is correct
5 Correct 1 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 1 ms 204 KB Output is correct
9 Correct 870 ms 46692 KB Output is correct
10 Correct 41 ms 4804 KB Output is correct
11 Correct 286 ms 24708 KB Output is correct
12 Correct 67 ms 7156 KB Output is correct
13 Correct 102 ms 15220 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 906 ms 45336 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 2464 ms 86028 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 1228 KB Output is correct
27 Correct 10 ms 1504 KB Output is correct
28 Correct 806 ms 33072 KB Output is correct
29 Correct 1354 ms 50996 KB Output is correct
30 Correct 1861 ms 66780 KB Output is correct
31 Correct 2389 ms 85744 KB Output is correct
32 Correct 0 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 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 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 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 1032 KB Output is correct
45 Runtime error 3064 ms 69596 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 0 ms 204 KB Output is correct
5 Correct 1 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 1 ms 204 KB Output is correct
9 Correct 870 ms 46692 KB Output is correct
10 Correct 41 ms 4804 KB Output is correct
11 Correct 286 ms 24708 KB Output is correct
12 Correct 67 ms 7156 KB Output is correct
13 Correct 102 ms 15220 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 906 ms 45336 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 3093 ms 132940 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 0 ms 204 KB Output is correct
5 Correct 1 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 1 ms 204 KB Output is correct
9 Correct 870 ms 46692 KB Output is correct
10 Correct 41 ms 4804 KB Output is correct
11 Correct 286 ms 24708 KB Output is correct
12 Correct 67 ms 7156 KB Output is correct
13 Correct 102 ms 15220 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 906 ms 45336 KB Output is correct
17 Correct 2099 ms 93500 KB Output is correct
18 Correct 2013 ms 97600 KB Output is correct
19 Runtime error 3127 ms 133216 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 0 ms 204 KB Output is correct
5 Correct 1 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 1 ms 204 KB Output is correct
9 Correct 870 ms 46692 KB Output is correct
10 Correct 41 ms 4804 KB Output is correct
11 Correct 286 ms 24708 KB Output is correct
12 Correct 67 ms 7156 KB Output is correct
13 Correct 102 ms 15220 KB Output is correct
14 Correct 2 ms 588 KB Output is correct
15 Correct 4 ms 844 KB Output is correct
16 Correct 906 ms 45336 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 2464 ms 86028 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 1228 KB Output is correct
27 Correct 10 ms 1504 KB Output is correct
28 Correct 806 ms 33072 KB Output is correct
29 Correct 1354 ms 50996 KB Output is correct
30 Correct 1861 ms 66780 KB Output is correct
31 Correct 2389 ms 85744 KB Output is correct
32 Correct 0 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 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 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 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 1032 KB Output is correct
45 Runtime error 3064 ms 69596 KB Execution killed with signal 6
46 Halted 0 ms 0 KB -