oj.uz

Submission #804254

# Submission time Handle Problem Language Result Execution time Memory
804254 2023-08-03T07:41:02 Z finn__ Fountain Parks (IOI21_parks) C++17
45 / 100
 346 ms 46808 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])
        {
            int x = dual_coords[v].first, y = dual_coords[v].second;

            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) * !(bool)(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 &&
                        ((cand.second == y && ((min(x, cand.first) & 3) == 1) ^ ((y & 3) == 3) ^ x > cand.first) ||
                         (cand.first == x && ((min(y, cand.second) & 3) == 1) ^ ((x & 3) == 3) ^ y > cand.second)))
                    {
                        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 &&
                    ((cand.second == y && ((min(x, cand.first) & 3) == 1) ^ ((y & 3) == 3) ^ x > cand.first) ||
                     (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 (j < n && 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 'void mark_cut_points(uint32_t)':
parks.cpp:73:100: warning: suggest parentheses around comparison in operand of '^' [-Wparentheses]
   73 |                         ((cand.second == y && ((min(x, cand.first) & 3) == 1) ^ ((y & 3) == 3) ^ x > cand.first) ||
      |                                                                                                  ~~^~~~~~~~~~~~
parks.cpp:74:100: warning: suggest parentheses around comparison in operand of '^' [-Wparentheses]
   74 |                          (cand.first == x && ((min(y, cand.second) & 3) == 1) ^ ((x & 3) == 3) ^ y > cand.second)))
      |                                                                                                  ~~^~~~~~~~~~~~~
parks.cpp: In function 'int construct_roads(std::vector<int>, std::vector<int>)':
parks.cpp:136:96: warning: suggest parentheses around comparison in operand of '^' [-Wparentheses]
  136 |                     ((cand.second == y && ((min(x, cand.first) & 3) == 1) ^ ((y & 3) == 3) ^ x > cand.first) ||
      |                                                                                              ~~^~~~~~~~~~~~
parks.cpp:137:96: warning: suggest parentheses around comparison in operand of '^' [-Wparentheses]
  137 |                      (cand.first == x && ((min(y, cand.second) & 3) == 1) ^ ((x & 3) == 3) ^ y > cand.second)))
      |                                                                                              ~~^~~~~~~~~~~~~
parks.cpp:186:23: warning: comparison of integer expressions of different signedness: 'int64_t' {aka 'long int'} and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
  186 |     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 3 ms 6484 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 3 ms 6544 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 82 ms 22252 KB Output is correct
10 Correct 8 ms 8152 KB Output is correct
11 Correct 40 ms 14912 KB Output is correct
12 Correct 12 ms 8920 KB Output is correct
13 Correct 19 ms 11152 KB Output is correct
14 Correct 3 ms 6612 KB Output is correct
15 Correct 4 ms 6740 KB Output is correct
16 Correct 81 ms 22180 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 3 ms 6484 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 3 ms 6544 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 82 ms 22252 KB Output is correct
10 Correct 8 ms 8152 KB Output is correct
11 Correct 40 ms 14912 KB Output is correct
12 Correct 12 ms 8920 KB Output is correct
13 Correct 19 ms 11152 KB Output is correct
14 Correct 3 ms 6612 KB Output is correct
15 Correct 4 ms 6740 KB Output is correct
16 Correct 81 ms 22180 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 6484 KB Output is correct
20 Correct 3 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 318 ms 46808 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 3 ms 6484 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 3 ms 6544 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 82 ms 22252 KB Output is correct
10 Correct 8 ms 8152 KB Output is correct
11 Correct 40 ms 14912 KB Output is correct
12 Correct 12 ms 8920 KB Output is correct
13 Correct 19 ms 11152 KB Output is correct
14 Correct 3 ms 6612 KB Output is correct
15 Correct 4 ms 6740 KB Output is correct
16 Correct 81 ms 22180 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 6484 KB Output is correct
20 Correct 3 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 318 ms 46808 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 3 ms 6484 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 3 ms 6544 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 82 ms 22252 KB Output is correct
10 Correct 8 ms 8152 KB Output is correct
11 Correct 40 ms 14912 KB Output is correct
12 Correct 12 ms 8920 KB Output is correct
13 Correct 19 ms 11152 KB Output is correct
14 Correct 3 ms 6612 KB Output is correct
15 Correct 4 ms 6740 KB Output is correct
16 Correct 81 ms 22180 KB Output is correct
17 Correct 3 ms 6484 KB Output is correct
18 Correct 3 ms 6516 KB Output is correct
19 Correct 3 ms 6484 KB Output is correct
20 Correct 258 ms 39012 KB Output is correct
21 Correct 247 ms 38888 KB Output is correct
22 Correct 266 ms 38880 KB Output is correct
23 Correct 197 ms 34192 KB Output is correct
24 Correct 146 ms 22220 KB Output is correct
25 Correct 236 ms 26388 KB Output is correct
26 Correct 163 ms 26496 KB Output is correct
27 Correct 206 ms 38712 KB Output is correct
28 Correct 227 ms 38080 KB Output is correct
29 Correct 324 ms 38156 KB Output is correct
30 Correct 260 ms 38164 KB Output is correct
31 Correct 3 ms 6484 KB Output is correct
32 Correct 22 ms 8860 KB Output is correct
33 Correct 65 ms 14376 KB Output is correct
34 Correct 228 ms 39104 KB Output is correct
35 Correct 9 ms 7640 KB Output is correct
36 Correct 43 ms 11612 KB Output is correct
37 Correct 92 ms 16568 KB Output is correct
38 Correct 92 ms 19776 KB Output is correct
39 Correct 133 ms 24228 KB Output is correct
40 Correct 189 ms 30132 KB Output is correct
41 Correct 231 ms 34328 KB Output is correct
42 Correct 268 ms 39612 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 6484 KB Output is correct
47 Correct 3 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 6456 KB Output is correct
51 Correct 4 ms 6532 KB Output is correct
52 Correct 4 ms 6484 KB Output is correct
53 Correct 3 ms 6484 KB Output is correct
54 Correct 5 ms 6740 KB Output is correct
55 Correct 5 ms 6920 KB Output is correct
56 Correct 104 ms 22288 KB Output is correct
57 Correct 171 ms 30168 KB Output is correct
58 Correct 151 ms 30300 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 209 ms 38120 KB Output is correct
63 Correct 205 ms 38192 KB Output is correct
64 Correct 198 ms 38080 KB Output is correct
65 Correct 5 ms 6996 KB Output is correct
66 Correct 9 ms 7404 KB Output is correct
67 Correct 112 ms 22220 KB Output is correct
68 Correct 170 ms 30896 KB Output is correct
69 Correct 307 ms 38200 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 3 ms 6484 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 3 ms 6544 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 82 ms 22252 KB Output is correct
10 Correct 8 ms 8152 KB Output is correct
11 Correct 40 ms 14912 KB Output is correct
12 Correct 12 ms 8920 KB Output is correct
13 Correct 19 ms 11152 KB Output is correct
14 Correct 3 ms 6612 KB Output is correct
15 Correct 4 ms 6740 KB Output is correct
16 Correct 81 ms 22180 KB Output is correct
17 Correct 238 ms 38592 KB Output is correct
18 Correct 225 ms 38688 KB Output is correct
19 Correct 249 ms 38868 KB Output is correct
20 Correct 280 ms 37532 KB Output is correct
21 Correct 240 ms 34304 KB Output is correct
22 Correct 3 ms 6484 KB Output is correct
23 Correct 41 ms 11804 KB Output is correct
24 Correct 17 ms 8784 KB Output is correct
25 Correct 63 ms 14172 KB Output is correct
26 Correct 123 ms 18048 KB Output is correct
27 Correct 136 ms 22756 KB Output is correct
28 Correct 178 ms 26512 KB Output is correct
29 Correct 271 ms 31768 KB Output is correct
30 Correct 244 ms 35208 KB Output is correct
31 Correct 346 ms 39064 KB Output is correct
32 Correct 266 ms 38144 KB Output is correct
33 Correct 179 ms 38104 KB Output is correct
34 Correct 6 ms 7124 KB Output is correct
35 Correct 10 ms 7636 KB Output is correct
36 Correct 107 ms 22400 KB Output is correct
37 Correct 194 ms 30968 KB Output is correct
38 Correct 303 ms 38192 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 3 ms 6484 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 3 ms 6544 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 82 ms 22252 KB Output is correct
10 Correct 8 ms 8152 KB Output is correct
11 Correct 40 ms 14912 KB Output is correct
12 Correct 12 ms 8920 KB Output is correct
13 Correct 19 ms 11152 KB Output is correct
14 Correct 3 ms 6612 KB Output is correct
15 Correct 4 ms 6740 KB Output is correct
16 Correct 81 ms 22180 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 6484 KB Output is correct
20 Correct 3 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 318 ms 46808 KB Tree @(3, 3) appears more than once: for edges on positions 1 and 2
24 Halted 0 ms 0 KB -