oj.uz

Submission #800788

# Submission time Handle Problem Language Result Execution time Memory
800788 2023-08-01T20:48:41 Z finn__ Fountain Parks (IOI21_parks) C++17
45 / 100
 266 ms 39744 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)
            {
                for (size_t i = 0; i < 4; ++i)
                {
                    pair<int, int> cand = {dual_coords[v].first - 2 + (i & 1) * 4,
                                           dual_coords[v].second - 2 + ((i & 2) >> 1) * 4};
                    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[u].first + cand.first) >> 1,
                                       (dual_coords[u].second + cand.second) >> 1);
                        break;
                    }
                }
            }
            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)
            dual[i].push_back(get<2>(*it)), dual[get<2>(*it)].push_back(i);
        it = midpoints.lower_bound({x, y + 2, 0});
        if (it != midpoints.end() && get<0>(*it) == x && get<1>(*it) == y + 2)
            dual[i].push_back(get<2>(*it)), dual[get<2>(*it)].push_back(i);
    }
    for (size_t i = 0; i < l; ++i)
        if (dual[i].size() < 4)
            dual[l].push_back(i), dual[i].push_back(l);
    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:151:23: warning: comparison of integer expressions of different signedness: 'int64_t' {aka 'long int'} and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
  151 |     if (d.set_size(0) != n)
      |         ~~~~~~~~~~~~~~^~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 6484 KB Output is correct
2 Correct 3 ms 6484 KB Output is correct
3 Correct 4 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 6512 KB Output is correct
8 Correct 3 ms 6484 KB Output is correct
9 Correct 82 ms 22328 KB Output is correct
10 Correct 9 ms 8280 KB Output is correct
11 Correct 39 ms 14968 KB Output is correct
12 Correct 12 ms 9048 KB Output is correct
13 Correct 19 ms 11264 KB Output is correct
14 Correct 4 ms 6740 KB Output is correct
15 Correct 4 ms 6740 KB Output is correct
16 Correct 85 ms 22320 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 6484 KB Output is correct
2 Correct 3 ms 6484 KB Output is correct
3 Correct 4 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 6512 KB Output is correct
8 Correct 3 ms 6484 KB Output is correct
9 Correct 82 ms 22328 KB Output is correct
10 Correct 9 ms 8280 KB Output is correct
11 Correct 39 ms 14968 KB Output is correct
12 Correct 12 ms 9048 KB Output is correct
13 Correct 19 ms 11264 KB Output is correct
14 Correct 4 ms 6740 KB Output is correct
15 Correct 4 ms 6740 KB Output is correct
16 Correct 85 ms 22320 KB Output is correct
17 Incorrect 3 ms 6484 KB Tree @(3, 3) appears more than once: for edges on positions 1 and 2
18 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 6484 KB Output is correct
2 Correct 3 ms 6484 KB Output is correct
3 Correct 4 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 6512 KB Output is correct
8 Correct 3 ms 6484 KB Output is correct
9 Correct 82 ms 22328 KB Output is correct
10 Correct 9 ms 8280 KB Output is correct
11 Correct 39 ms 14968 KB Output is correct
12 Correct 12 ms 9048 KB Output is correct
13 Correct 19 ms 11264 KB Output is correct
14 Correct 4 ms 6740 KB Output is correct
15 Correct 4 ms 6740 KB Output is correct
16 Correct 85 ms 22320 KB Output is correct
17 Incorrect 3 ms 6484 KB Tree @(3, 3) appears more than once: for edges on positions 1 and 2
18 Halted 0 ms 0 KB -

Subtask #4
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 6484 KB Output is correct
2 Correct 3 ms 6484 KB Output is correct
3 Correct 4 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 6512 KB Output is correct
8 Correct 3 ms 6484 KB Output is correct
9 Correct 82 ms 22328 KB Output is correct
10 Correct 9 ms 8280 KB Output is correct
11 Correct 39 ms 14968 KB Output is correct
12 Correct 12 ms 9048 KB Output is correct
13 Correct 19 ms 11264 KB Output is correct
14 Correct 4 ms 6740 KB Output is correct
15 Correct 4 ms 6740 KB Output is correct
16 Correct 85 ms 22320 KB Output is correct
17 Correct 3 ms 6484 KB Output is correct
18 Correct 3 ms 6580 KB Output is correct
19 Correct 3 ms 6484 KB Output is correct
20 Correct 248 ms 39188 KB Output is correct
21 Correct 251 ms 39016 KB Output is correct
22 Correct 250 ms 38928 KB Output is correct
23 Correct 183 ms 34296 KB Output is correct
24 Correct 139 ms 22328 KB Output is correct
25 Correct 214 ms 26556 KB Output is correct
26 Correct 150 ms 26568 KB Output is correct
27 Correct 228 ms 38700 KB Output is correct
28 Correct 223 ms 38292 KB Output is correct
29 Correct 254 ms 38292 KB Output is correct
30 Correct 266 ms 38236 KB Output is correct
31 Correct 3 ms 6484 KB Output is correct
32 Correct 19 ms 9016 KB Output is correct
33 Correct 65 ms 14432 KB Output is correct
34 Correct 232 ms 39176 KB Output is correct
35 Correct 9 ms 7836 KB Output is correct
36 Correct 46 ms 11772 KB Output is correct
37 Correct 89 ms 16708 KB Output is correct
38 Correct 95 ms 19992 KB Output is correct
39 Correct 129 ms 24284 KB Output is correct
40 Correct 168 ms 30320 KB Output is correct
41 Correct 209 ms 34420 KB Output is correct
42 Correct 258 ms 39744 KB Output is correct
43 Correct 3 ms 6484 KB Output is correct
44 Correct 3 ms 6484 KB Output is correct
45 Correct 3 ms 6484 KB Output is correct
46 Correct 3 ms 6580 KB Output is correct
47 Correct 3 ms 6484 KB Output is correct
48 Correct 3 ms 6560 KB Output is correct
49 Correct 3 ms 6580 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 98 ms 22432 KB Output is correct
57 Correct 167 ms 30200 KB Output is correct
58 Correct 146 ms 30336 KB Output is correct
59 Correct 3 ms 6484 KB Output is correct
60 Correct 3 ms 6580 KB Output is correct
61 Correct 3 ms 6484 KB Output is correct
62 Correct 171 ms 38268 KB Output is correct
63 Correct 172 ms 38308 KB Output is correct
64 Correct 174 ms 38180 KB Output is correct
65 Correct 6 ms 6980 KB Output is correct
66 Correct 7 ms 7508 KB Output is correct
67 Correct 99 ms 22368 KB Output is correct
68 Correct 162 ms 31096 KB Output is correct
69 Correct 216 ms 38268 KB Output is correct

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 6484 KB Output is correct
2 Correct 3 ms 6484 KB Output is correct
3 Correct 4 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 6512 KB Output is correct
8 Correct 3 ms 6484 KB Output is correct
9 Correct 82 ms 22328 KB Output is correct
10 Correct 9 ms 8280 KB Output is correct
11 Correct 39 ms 14968 KB Output is correct
12 Correct 12 ms 9048 KB Output is correct
13 Correct 19 ms 11264 KB Output is correct
14 Correct 4 ms 6740 KB Output is correct
15 Correct 4 ms 6740 KB Output is correct
16 Correct 85 ms 22320 KB Output is correct
17 Correct 207 ms 38724 KB Output is correct
18 Correct 230 ms 38872 KB Output is correct
19 Correct 248 ms 38928 KB Output is correct
20 Correct 250 ms 37664 KB Output is correct
21 Correct 226 ms 34456 KB Output is correct
22 Correct 3 ms 6484 KB Output is correct
23 Correct 37 ms 11828 KB Output is correct
24 Correct 18 ms 8892 KB Output is correct
25 Correct 61 ms 14336 KB Output is correct
26 Correct 114 ms 18296 KB Output is correct
27 Correct 125 ms 22804 KB Output is correct
28 Correct 152 ms 26608 KB Output is correct
29 Correct 201 ms 31900 KB Output is correct
30 Correct 221 ms 35260 KB Output is correct
31 Correct 256 ms 39192 KB Output is correct
32 Correct 240 ms 38280 KB Output is correct
33 Correct 172 ms 38344 KB Output is correct
34 Correct 5 ms 7188 KB Output is correct
35 Correct 10 ms 7740 KB Output is correct
36 Correct 103 ms 22576 KB Output is correct
37 Correct 162 ms 31060 KB Output is correct
38 Correct 220 ms 38384 KB Output is correct

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 6484 KB Output is correct
2 Correct 3 ms 6484 KB Output is correct
3 Correct 4 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 6512 KB Output is correct
8 Correct 3 ms 6484 KB Output is correct
9 Correct 82 ms 22328 KB Output is correct
10 Correct 9 ms 8280 KB Output is correct
11 Correct 39 ms 14968 KB Output is correct
12 Correct 12 ms 9048 KB Output is correct
13 Correct 19 ms 11264 KB Output is correct
14 Correct 4 ms 6740 KB Output is correct
15 Correct 4 ms 6740 KB Output is correct
16 Correct 85 ms 22320 KB Output is correct
17 Incorrect 3 ms 6484 KB Tree @(3, 3) appears more than once: for edges on positions 1 and 2
18 Halted 0 ms 0 KB -