oj.uz

Submission #800805

# Submission time Handle Problem Language Result Execution time Memory
800805 2023-08-01T21:22:25 Z finn__ Fountain Parks (IOI21_parks) C++17
45 / 100
 295 ms 48400 KB 
#include "parks.h"
#include <bits/stdc++.h>
using namespace std;

template <size_t N>
struct dsu
{
    int64_t p[N];

    dsu() { fill(p, p + N, -1); }

    int64_t repr(int64_t u) { return p[u] < 0 ? u : p[u] = repr(p[u]); }

    bool merge(int64_t i, int64_t j)
    {
        i = repr(i);
        j = repr(j);
        if (i == j)
            return 0;

        if (p[i] > p[j])
            swap(i, j);
        p[i] += p[j];
        p[j] = i;
        return 1;
    }

    bool same_set(int64_t i, int64_t j) { return repr(i) == repr(j); }

    int64_t set_size(int64_t i) { return -p[repr(i)]; }

    void reset() { fill(p.begin(), p.end(), -1); }
};

struct fountain
{
    int x, y;
    size_t i;
};

constexpr size_t N = 200000;

fountain f[N];
vector<pair<size_t, size_t>> edges;
vector<uint32_t> dual[N];
dsu<N> d;
set<pair<int, int>> points, marked;
set<tuple<int, int, uint32_t>> midpoints;
pair<int, int> dual_coords[N];
bitset<N> visited;
size_t l;

void mark_cut_points(uint32_t u)
{
    visited[u] = 1;
    for (auto const &v : dual[u])
        if (!visited[v])
        {
            if (u == l)
            {
                bool placed = 0;
                for (size_t i = 0; i < 4; ++i)
                {
                    pair<int, int> cand = {dual_coords[v].first + (-2 + (i & 1) * 4) * !(i & 2),
                                           dual_coords[v].second + (-2 + (i & 1) * 4) * (bool)(i & 2)};
                    bool not_present = 1;
                    for (auto const &w : dual[v])
                        if (w != u)
                            not_present &= dual_coords[w] != cand;
                    if (not_present)
                    {
                        marked.emplace((dual_coords[v].first + cand.first) >> 1,
                                       (dual_coords[v].second + cand.second) >> 1);
                        placed = 1;
                        break;
                    }
                }
                assert(placed);
            }
            else
            {
                marked.emplace((dual_coords[u].first + dual_coords[v].first) >> 1,
                               (dual_coords[u].second + dual_coords[v].second) >> 1);
            }
            mark_cut_points(v);
        }
}

int construct_roads(vector<int> x, vector<int> y)
{
    size_t n = x.size();

    for (size_t i = 0; i < n; ++i)
        points.emplace(x[i], y[i]);
    for (size_t i = 0; i < n; ++i)
        if (points.find({x[i] + 2, y[i]}) != points.end() &&
            points.find({x[i], y[i] + 2}) != points.end() &&
            points.find({x[i] + 2, y[i] + 2}) != points.end())
            midpoints.emplace(x[i] + 1, y[i] + 1, l++), dual_coords[l - 1] = {x[i] + 1, y[i] + 1};
    for (auto const &[x, y, i] : midpoints)
    {
        auto it = midpoints.lower_bound({x + 2, y, 0});
        if (it != midpoints.end() && get<0>(*it) == x + 2 && get<1>(*it) == y)
        {
            if (((x & 3) == 1) ^ ((y & 3) == 3))
                dual[get<2>(*it)].push_back(i);
            else
                dual[i].push_back(get<2>(*it));
        }
        it = midpoints.lower_bound({x, y + 2, 0});
        if (it != midpoints.end() && get<0>(*it) == x && get<1>(*it) == y + 2)
        {
            if (((y & 3) == 1) ^ ((x & 3) == 3))
                dual[i].push_back(get<2>(*it));
            else
                dual[get<2>(*it)].push_back(i);
        }
    }
    for (size_t i = 0; i < l; ++i)
        if (dual[i].size() < 4)
        {
            int x = dual_coords[i].first, y = dual_coords[i].second;
            for (size_t i = 0; i < 4; ++i)
            {
                pair<int, int> cand = {dual_coords[i].first + (-2 + (i & 1) * 4) * !(i & 2),
                                       dual_coords[i].second + (-2 + (i & 1) * 4) * (bool)(i & 2)};
                bool not_present = 1;
                for (auto const &w : dual[i])
                    if (w != l)
                        not_present &= dual_coords[w] != cand;
                if (not_present)
                {
                    if (cand.second == y && ((min(x, cand.first) & 3) == 1) ^ ((y & 3) == 3) ^ x > cand.first)
                    {
                        dual[l].push_back(i);
                        break;
                    }
                    if (cand.first == x && ((min(y, cand.second) & 3) == 1) ^ ((x & 3) == 3) ^ y > cand.second)
                    {
                        dual[l].push_back(i);
                        break;
                    }
                }
            }
        }
    mark_cut_points(l);

    for (size_t i = 0; i < x.size(); ++i)
        f[i].i = i, f[i].x = x[i], f[i].y = y[i];
    sort(f, f + n, [](auto const &a, auto const &b)
         { return a.y == b.y ? a.x < b.x : a.y < b.y; });

    for (size_t i = 0; i < n;)
    {
        size_t j = i;
        while (j < n && f[j].y == f[i].y)
            ++j;

        for (size_t k = i + 1; k < j; ++k)
            if (f[k - 1].x + 2 == f[k].x)
                if (marked.find({f[k - 1].x + 1, f[k - 1].y}) == marked.end() &&
                    d.merge(f[k - 1].i, f[k].i))
                    edges.emplace_back(f[k - 1].i, f[k].i);

        if (f[j].y == f[i].y + 2)
        {
            size_t k = j;
            while (i < j && k < n && f[k].y == f[j].y)
            {
                if (f[i].x < f[k].x)
                    ++i;
                else if (f[k].x < f[i].x)
                    ++k;
                else
                {
                    if (marked.find({f[i].x, f[i].y + 1}) == marked.end() &&
                        d.merge(f[i].i, f[k].i))
                        edges.emplace_back(f[k].i, f[i].i);
                    ++i;
                    ++k;
                }
            }
        }

        i = j;
    }

    if (d.set_size(0) != n)
        return 0;
    vector<int> u, v, a, b;
    for (auto const &[i, j] : edges)
    {
        u.push_back(i);
        v.push_back(j);
        if (x[i] == x[j])
        {
            b.push_back((y[i] + y[j]) >> 1);
            if (((x[i] & 3) == 2) ^ ((min(y[i], y[j]) & 3) == 2))
                a.push_back(x[i] - 1);
            else
                a.push_back(x[i] + 1);
        }
        else
        {
            a.push_back((x[i] + x[j]) >> 1);
            if (((y[i] & 3) == 2) ^ ((min(x[i], x[j]) & 3) == 2))
                b.push_back(y[i] + 1);
            else
                b.push_back(y[i] - 1);
        }
    }

    build(u, v, a, b);
    return 1;
}

Compilation message

parks.cpp: In function 'int construct_roads(std::vector<int>, std::vector<int>)':
parks.cpp:133:98: warning: suggest parentheses around comparison in operand of '^' [-Wparentheses]
  133 |                     if (cand.second == y && ((min(x, cand.first) & 3) == 1) ^ ((y & 3) == 3) ^ x > cand.first)
      |                                                                                                ~~^~~~~~~~~~~~
parks.cpp:138:98: warning: suggest parentheses around comparison in operand of '^' [-Wparentheses]
  138 |                     if (cand.first == x && ((min(y, cand.second) & 3) == 1) ^ ((x & 3) == 3) ^ y > cand.second)
      |                                                                                                ~~^~~~~~~~~~~~~
parks.cpp:188:23: warning: comparison of integer expressions of different signedness: 'int64_t' {aka 'long int'} and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
  188 |     if (d.set_size(0) != n)
      |         ~~~~~~~~~~~~~~^~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 6484 KB Output is correct
2 Correct 2 ms 6484 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 3 ms 6484 KB Output is correct
5 Correct 3 ms 6484 KB Output is correct
6 Correct 3 ms 6484 KB Output is correct
7 Correct 3 ms 6484 KB Output is correct
8 Correct 3 ms 6484 KB Output is correct
9 Correct 79 ms 22260 KB Output is correct
10 Correct 8 ms 8204 KB Output is correct
11 Correct 37 ms 14932 KB Output is correct
12 Correct 11 ms 8944 KB Output is correct
13 Correct 19 ms 11120 KB Output is correct
14 Correct 3 ms 6612 KB Output is correct
15 Correct 3 ms 6740 KB Output is correct
16 Correct 79 ms 22184 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 6484 KB Output is correct
2 Correct 2 ms 6484 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 3 ms 6484 KB Output is correct
5 Correct 3 ms 6484 KB Output is correct
6 Correct 3 ms 6484 KB Output is correct
7 Correct 3 ms 6484 KB Output is correct
8 Correct 3 ms 6484 KB Output is correct
9 Correct 79 ms 22260 KB Output is correct
10 Correct 8 ms 8204 KB Output is correct
11 Correct 37 ms 14932 KB Output is correct
12 Correct 11 ms 8944 KB Output is correct
13 Correct 19 ms 11120 KB Output is correct
14 Correct 3 ms 6612 KB Output is correct
15 Correct 3 ms 6740 KB Output is correct
16 Correct 79 ms 22184 KB Output is correct
17 Correct 3 ms 6484 KB Output is correct
18 Correct 3 ms 6576 KB Output is correct
19 Correct 3 ms 6484 KB Output is correct
20 Correct 4 ms 6484 KB Output is correct
21 Correct 3 ms 6484 KB Output is correct
22 Correct 3 ms 6484 KB Output is correct
23 Incorrect 295 ms 48400 KB Tree @(3, 3) appears more than once: for edges on positions 1 and 2
24 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 6484 KB Output is correct
2 Correct 2 ms 6484 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 3 ms 6484 KB Output is correct
5 Correct 3 ms 6484 KB Output is correct
6 Correct 3 ms 6484 KB Output is correct
7 Correct 3 ms 6484 KB Output is correct
8 Correct 3 ms 6484 KB Output is correct
9 Correct 79 ms 22260 KB Output is correct
10 Correct 8 ms 8204 KB Output is correct
11 Correct 37 ms 14932 KB Output is correct
12 Correct 11 ms 8944 KB Output is correct
13 Correct 19 ms 11120 KB Output is correct
14 Correct 3 ms 6612 KB Output is correct
15 Correct 3 ms 6740 KB Output is correct
16 Correct 79 ms 22184 KB Output is correct
17 Correct 3 ms 6484 KB Output is correct
18 Correct 3 ms 6576 KB Output is correct
19 Correct 3 ms 6484 KB Output is correct
20 Correct 4 ms 6484 KB Output is correct
21 Correct 3 ms 6484 KB Output is correct
22 Correct 3 ms 6484 KB Output is correct
23 Incorrect 295 ms 48400 KB Tree @(3, 3) appears more than once: for edges on positions 1 and 2
24 Halted 0 ms 0 KB -

Subtask #4
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 6484 KB Output is correct
2 Correct 2 ms 6484 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 3 ms 6484 KB Output is correct
5 Correct 3 ms 6484 KB Output is correct
6 Correct 3 ms 6484 KB Output is correct
7 Correct 3 ms 6484 KB Output is correct
8 Correct 3 ms 6484 KB Output is correct
9 Correct 79 ms 22260 KB Output is correct
10 Correct 8 ms 8204 KB Output is correct
11 Correct 37 ms 14932 KB Output is correct
12 Correct 11 ms 8944 KB Output is correct
13 Correct 19 ms 11120 KB Output is correct
14 Correct 3 ms 6612 KB Output is correct
15 Correct 3 ms 6740 KB Output is correct
16 Correct 79 ms 22184 KB Output is correct
17 Correct 3 ms 6484 KB Output is correct
18 Correct 3 ms 6484 KB Output is correct
19 Correct 3 ms 6556 KB Output is correct
20 Correct 258 ms 39028 KB Output is correct
21 Correct 232 ms 38772 KB Output is correct
22 Correct 254 ms 38880 KB Output is correct
23 Correct 192 ms 34156 KB Output is correct
24 Correct 147 ms 22224 KB Output is correct
25 Correct 226 ms 26424 KB Output is correct
26 Correct 158 ms 26436 KB Output is correct
27 Correct 203 ms 38544 KB Output is correct
28 Correct 234 ms 38116 KB Output is correct
29 Correct 283 ms 38076 KB Output is correct
30 Correct 261 ms 38160 KB Output is correct
31 Correct 3 ms 6484 KB Output is correct
32 Correct 17 ms 8844 KB Output is correct
33 Correct 66 ms 14280 KB Output is correct
34 Correct 216 ms 39068 KB Output is correct
35 Correct 9 ms 7640 KB Output is correct
36 Correct 44 ms 11544 KB Output is correct
37 Correct 98 ms 16544 KB Output is correct
38 Correct 95 ms 19772 KB Output is correct
39 Correct 132 ms 24220 KB Output is correct
40 Correct 180 ms 30144 KB Output is correct
41 Correct 233 ms 34296 KB Output is correct
42 Correct 274 ms 39636 KB Output is correct
43 Correct 4 ms 6484 KB Output is correct
44 Correct 4 ms 6484 KB Output is correct
45 Correct 3 ms 6484 KB Output is correct
46 Correct 3 ms 6484 KB Output is correct
47 Correct 4 ms 6484 KB Output is correct
48 Correct 3 ms 6484 KB Output is correct
49 Correct 3 ms 6484 KB Output is correct
50 Correct 3 ms 6484 KB Output is correct
51 Correct 3 ms 6484 KB Output is correct
52 Correct 3 ms 6484 KB Output is correct
53 Correct 3 ms 6484 KB Output is correct
54 Correct 4 ms 6740 KB Output is correct
55 Correct 4 ms 6868 KB Output is correct
56 Correct 96 ms 22204 KB Output is correct
57 Correct 146 ms 30148 KB Output is correct
58 Correct 145 ms 30304 KB Output is correct
59 Correct 3 ms 6484 KB Output is correct
60 Correct 3 ms 6484 KB Output is correct
61 Correct 3 ms 6484 KB Output is correct
62 Correct 174 ms 38128 KB Output is correct
63 Correct 169 ms 38164 KB Output is correct
64 Correct 170 ms 38052 KB Output is correct
65 Correct 5 ms 6996 KB Output is correct
66 Correct 7 ms 7380 KB Output is correct
67 Correct 101 ms 22160 KB Output is correct
68 Correct 159 ms 31080 KB Output is correct
69 Correct 216 ms 38280 KB Output is correct

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 6484 KB Output is correct
2 Correct 2 ms 6484 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 3 ms 6484 KB Output is correct
5 Correct 3 ms 6484 KB Output is correct
6 Correct 3 ms 6484 KB Output is correct
7 Correct 3 ms 6484 KB Output is correct
8 Correct 3 ms 6484 KB Output is correct
9 Correct 79 ms 22260 KB Output is correct
10 Correct 8 ms 8204 KB Output is correct
11 Correct 37 ms 14932 KB Output is correct
12 Correct 11 ms 8944 KB Output is correct
13 Correct 19 ms 11120 KB Output is correct
14 Correct 3 ms 6612 KB Output is correct
15 Correct 3 ms 6740 KB Output is correct
16 Correct 79 ms 22184 KB Output is correct
17 Correct 214 ms 38560 KB Output is correct
18 Correct 231 ms 38716 KB Output is correct
19 Correct 235 ms 38804 KB Output is correct
20 Correct 250 ms 37480 KB Output is correct
21 Correct 206 ms 34332 KB Output is correct
22 Correct 3 ms 6516 KB Output is correct
23 Correct 40 ms 11696 KB Output is correct
24 Correct 17 ms 8776 KB Output is correct
25 Correct 61 ms 14164 KB Output is correct
26 Correct 110 ms 18116 KB Output is correct
27 Correct 118 ms 22692 KB Output is correct
28 Correct 151 ms 26572 KB Output is correct
29 Correct 184 ms 31792 KB Output is correct
30 Correct 234 ms 35200 KB Output is correct
31 Correct 253 ms 39104 KB Output is correct
32 Correct 220 ms 38124 KB Output is correct
33 Correct 169 ms 38164 KB Output is correct
34 Correct 5 ms 7124 KB Output is correct
35 Correct 7 ms 7636 KB Output is correct
36 Correct 112 ms 22336 KB Output is correct
37 Correct 173 ms 30992 KB Output is correct
38 Correct 225 ms 38232 KB Output is correct

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 6484 KB Output is correct
2 Correct 2 ms 6484 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 3 ms 6484 KB Output is correct
5 Correct 3 ms 6484 KB Output is correct
6 Correct 3 ms 6484 KB Output is correct
7 Correct 3 ms 6484 KB Output is correct
8 Correct 3 ms 6484 KB Output is correct
9 Correct 79 ms 22260 KB Output is correct
10 Correct 8 ms 8204 KB Output is correct
11 Correct 37 ms 14932 KB Output is correct
12 Correct 11 ms 8944 KB Output is correct
13 Correct 19 ms 11120 KB Output is correct
14 Correct 3 ms 6612 KB Output is correct
15 Correct 3 ms 6740 KB Output is correct
16 Correct 79 ms 22184 KB Output is correct
17 Correct 3 ms 6484 KB Output is correct
18 Correct 3 ms 6576 KB Output is correct
19 Correct 3 ms 6484 KB Output is correct
20 Correct 4 ms 6484 KB Output is correct
21 Correct 3 ms 6484 KB Output is correct
22 Correct 3 ms 6484 KB Output is correct
23 Incorrect 295 ms 48400 KB Tree @(3, 3) appears more than once: for edges on positions 1 and 2
24 Halted 0 ms 0 KB -