oj.uz

Submission #442802

# Submission time Handle Problem Language Result Execution time Memory
442802 2021-07-09T06:33:52 Z palilo Network (BOI15_net) C++17
100 / 100
 501 ms 45960 KB 
#include <bits/stdc++.h>
using namespace std;

namespace std {
// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0200r0.html
template <class Fun>
class y_combinator_result {
    Fun fun_;

public:
    template <class T>
    explicit y_combinator_result(T&& fun) : fun_(std::forward<T>(fun)) {}

    template <class... Args>
    decltype(auto) operator()(Args&&... args) {
        return fun_(std::ref(*this), std::forward<Args>(args)...);
    }
};

template <class Fun>
decltype(auto) y_combinator(Fun&& fun) {
    return y_combinator_result<std::decay_t<Fun>>(std::forward<Fun>(fun));
}
}; // namespace std

int main() {
    cin.tie(nullptr)->sync_with_stdio(false);
#ifdef palilo
    freopen("in", "r", stdin);
    freopen("out", "w", stdout);
#endif
    int n;
    cin >> n;
    vector<vector<int>> adj(n);
    for (int u, v, i = n - 1; i--;) {
        cin >> u >> v, --u, --v;
        adj[u].emplace_back(v);
        adj[v].emplace_back(u);
    }
    const int root = find_if(adj.begin(), adj.end(), [&](const auto& x) {
        return x.size() != 1;
    }) - adj.begin();
    vector<int> leaves;
    y_combinator([&](auto self, int u) -> void {
        if (adj[u].empty()) {
            leaves.emplace_back(u);
        } else {
            for (const auto& v : adj[u]) {
                adj[v].erase(find(adj[v].begin(), adj[v].end(), u));
                self(v);
            }
        }
    })(root);
    cout << (leaves.size() + 1) / 2 << '\n';
    for (int i = 0; i < (leaves.size() + 1) / 2; ++i) {
        cout << leaves[i] + 1 << ' ' << leaves[i + leaves.size() / 2] + 1 << '\n';
    }
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:55:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   55 |     for (int i = 0; i < (leaves.size() + 1) / 2; ++i) {
      |                     ~~^~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

# 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 0 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 0 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 1 ms 316 KB Output is correct
12 Correct 0 ms 204 KB Output is correct
13 Correct 0 ms 204 KB Output is correct
14 Correct 1 ms 204 KB Output is correct
15 Correct 1 ms 204 KB Output is correct
16 Correct 0 ms 312 KB Output is correct
17 Correct 1 ms 204 KB Output is correct
18 Correct 1 ms 204 KB Output is correct
19 Correct 0 ms 204 KB Output is correct
20 Correct 0 ms 204 KB Output is correct

Subtask #2
45.0 / 45.0

# 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 0 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 0 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 1 ms 316 KB Output is correct
12 Correct 0 ms 204 KB Output is correct
13 Correct 0 ms 204 KB Output is correct
14 Correct 1 ms 204 KB Output is correct
15 Correct 1 ms 204 KB Output is correct
16 Correct 0 ms 312 KB Output is correct
17 Correct 1 ms 204 KB Output is correct
18 Correct 1 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 1 ms 204 KB Output is correct
22 Correct 1 ms 456 KB Output is correct
23 Correct 1 ms 460 KB Output is correct
24 Correct 1 ms 460 KB Output is correct
25 Correct 1 ms 460 KB Output is correct
26 Correct 1 ms 332 KB Output is correct
27 Correct 1 ms 444 KB Output is correct
28 Correct 1 ms 460 KB Output is correct
29 Correct 1 ms 324 KB Output is correct
30 Correct 1 ms 204 KB Output is correct
31 Correct 1 ms 448 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 1 ms 204 KB Output is correct
36 Correct 1 ms 204 KB Output is correct
37 Correct 1 ms 332 KB Output is correct
38 Correct 1 ms 332 KB Output is correct
39 Correct 1 ms 204 KB Output is correct
40 Correct 1 ms 204 KB Output is correct
41 Correct 1 ms 204 KB Output is correct
42 Correct 1 ms 332 KB Output is correct
43 Correct 1 ms 332 KB Output is correct
44 Correct 1 ms 204 KB Output is correct
45 Correct 1 ms 332 KB Output is correct
46 Correct 1 ms 332 KB Output is correct
47 Correct 0 ms 204 KB Output is correct
48 Correct 1 ms 332 KB Output is correct
49 Correct 1 ms 388 KB Output is correct
50 Correct 0 ms 204 KB Output is correct
51 Correct 0 ms 204 KB Output is correct
52 Correct 1 ms 332 KB Output is correct
53 Correct 1 ms 332 KB Output is correct
54 Correct 0 ms 204 KB Output is correct
55 Correct 1 ms 332 KB Output is correct
56 Correct 1 ms 204 KB Output is correct
57 Correct 1 ms 332 KB Output is correct
58 Correct 1 ms 444 KB Output is correct

Subtask #3
37.0 / 37.0

# 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 0 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 0 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 1 ms 316 KB Output is correct
12 Correct 0 ms 204 KB Output is correct
13 Correct 0 ms 204 KB Output is correct
14 Correct 1 ms 204 KB Output is correct
15 Correct 1 ms 204 KB Output is correct
16 Correct 0 ms 312 KB Output is correct
17 Correct 1 ms 204 KB Output is correct
18 Correct 1 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 1 ms 204 KB Output is correct
22 Correct 1 ms 456 KB Output is correct
23 Correct 1 ms 460 KB Output is correct
24 Correct 1 ms 460 KB Output is correct
25 Correct 1 ms 460 KB Output is correct
26 Correct 1 ms 332 KB Output is correct
27 Correct 1 ms 444 KB Output is correct
28 Correct 1 ms 460 KB Output is correct
29 Correct 1 ms 324 KB Output is correct
30 Correct 1 ms 204 KB Output is correct
31 Correct 1 ms 448 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 1 ms 204 KB Output is correct
36 Correct 1 ms 204 KB Output is correct
37 Correct 1 ms 332 KB Output is correct
38 Correct 1 ms 332 KB Output is correct
39 Correct 1 ms 204 KB Output is correct
40 Correct 1 ms 204 KB Output is correct
41 Correct 1 ms 204 KB Output is correct
42 Correct 1 ms 332 KB Output is correct
43 Correct 1 ms 332 KB Output is correct
44 Correct 1 ms 204 KB Output is correct
45 Correct 1 ms 332 KB Output is correct
46 Correct 1 ms 332 KB Output is correct
47 Correct 0 ms 204 KB Output is correct
48 Correct 1 ms 332 KB Output is correct
49 Correct 1 ms 388 KB Output is correct
50 Correct 0 ms 204 KB Output is correct
51 Correct 0 ms 204 KB Output is correct
52 Correct 1 ms 332 KB Output is correct
53 Correct 1 ms 332 KB Output is correct
54 Correct 0 ms 204 KB Output is correct
55 Correct 1 ms 332 KB Output is correct
56 Correct 1 ms 204 KB Output is correct
57 Correct 1 ms 332 KB Output is correct
58 Correct 1 ms 444 KB Output is correct
59 Correct 384 ms 34796 KB Output is correct
60 Correct 492 ms 38720 KB Output is correct
61 Correct 1 ms 204 KB Output is correct
62 Correct 0 ms 204 KB Output is correct
63 Correct 333 ms 31240 KB Output is correct
64 Correct 2 ms 716 KB Output is correct
65 Correct 11 ms 2636 KB Output is correct
66 Correct 137 ms 19284 KB Output is correct
67 Correct 501 ms 45284 KB Output is correct
68 Correct 492 ms 45960 KB Output is correct
69 Correct 7 ms 1484 KB Output is correct
70 Correct 87 ms 13288 KB Output is correct
71 Correct 328 ms 41908 KB Output is correct
72 Correct 356 ms 40696 KB Output is correct
73 Correct 91 ms 10624 KB Output is correct
74 Correct 481 ms 37608 KB Output is correct
75 Correct 24 ms 4800 KB Output is correct
76 Correct 336 ms 41496 KB Output is correct
77 Correct 340 ms 41640 KB Output is correct
78 Correct 26 ms 4940 KB Output is correct
79 Correct 478 ms 43732 KB Output is correct
80 Correct 2 ms 588 KB Output is correct
81 Correct 107 ms 13648 KB Output is correct
82 Correct 409 ms 39608 KB Output is correct
83 Correct 456 ms 37704 KB Output is correct
84 Correct 458 ms 37660 KB Output is correct
85 Correct 461 ms 37704 KB Output is correct
86 Correct 458 ms 38692 KB Output is correct
87 Correct 462 ms 38968 KB Output is correct