Submission #583425

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
583425	2022-06-25T10:47:47 Z	TheLimePixel	Network (BOI15_net)	C++17	100 / 100	542 ms	47140 KB

#include "bits/stdc++.h"

using namespace std;

vector<vector<int>> graph;
vector<int> leaves_from; // Brojot na listovi vo sekoe poddrvo
vector<int> leaves; // indeksite na listovite
int leaf_count, res_count; // Brojot na listovi i brojt na potrebni vrski

// Funkcija koja rekurentno gi broi listovite vo sekoe poddrvo
void count_leaves(int node, int parent) {
    if (graph[node].size() == 1)
       leaves_from[node] = 1;

    for (auto adj : graph[node]) {
        if (adj == parent) 
            continue; 

        count_leaves(adj, node);
        leaves_from[node] += leaves_from[adj];
    }
} 

// Funkcija za baranje na srednoto teme
int find_mid(int node) {
    int parent = 0;

    for (auto adj : graph[node])
        if (adj != parent && leaves_from[adj] > leaf_count / 2) {
            parent = node;
            node = adj;
        }

  return node;
}

// Funkcija koja rekurentno gi dodava listovite
void add_leaves(int node, int parent) {
    if (graph[node].size() == 1)
        leaves.push_back(node);

    for (auto adj : graph[node])
        if (adj != parent)
            add_leaves(adj, node);
}

// Funkcija koja go deli drvoto na poddrva i gi dodava nivnite listovi na nizata
int split(int n) {
    count_leaves(1, 0);

    int mid = find_mid(1);

    for (auto adj : graph[mid])
        add_leaves(adj, mid);

    return mid;
}


// Glavnata funkcija
void run() {
    int n;
    cin >> n;

    // Se spravuvame so posebni sluchai

    if (n == 1) {
        cout << 0;
        return;
    }

    if (n == 2) {
        cout << "1\n2";
        return;
    }

    graph = vector<vector<int>>(n + 1);
    leaves_from = vector<int>(n + 1);

    // Go inicijalizirame drvoto

    for (int i = 0; i < n - 1; i++) {
        int a, b;
        cin >> a >> b;
        graph[a].push_back(b);
        graph[b].push_back(a);
    }

    // Gi broime listovite, a so toa i brojot na potrebni vrski

    for (int i = 1; i <= n; i++)
        if (graph[i].size() == 1)
            leaf_count++;

    res_count = (leaf_count + 1) / 2;
    cout << res_count;
    leaves.reserve(2 * res_count);

    // Go delime drvoto na poddrva i gi dodavame nivnite listovi

    split(n);

    if (leaf_count & 1)
        leaves.push_back(leaves.front());

    // Gi pechatime soodvetnite parovi na listovi

    for (int i = 0; i < res_count; i++)
        cout << '\n' << leaves[i] << ' ' << leaves[res_count + i];
}

// Main funkcija
auto main() -> int {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    run();
}

Subtask #1
18.0 / 18.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	212 KB	Output is correct
2	Correct	1 ms	212 KB	Output is correct
3	Correct	1 ms	212 KB	Output is correct
4	Correct	0 ms	212 KB	Output is correct
5	Correct	1 ms	212 KB	Output is correct
6	Correct	1 ms	212 KB	Output is correct
7	Correct	1 ms	212 KB	Output is correct
8	Correct	1 ms	212 KB	Output is correct
9	Correct	1 ms	212 KB	Output is correct
10	Correct	0 ms	212 KB	Output is correct
11	Correct	0 ms	212 KB	Output is correct
12	Correct	0 ms	212 KB	Output is correct
13	Correct	0 ms	212 KB	Output is correct
14	Correct	1 ms	212 KB	Output is correct
15	Correct	0 ms	212 KB	Output is correct
16	Correct	0 ms	212 KB	Output is correct
17	Correct	0 ms	212 KB	Output is correct
18	Correct	0 ms	212 KB	Output is correct
19	Correct	0 ms	212 KB	Output is correct
20	Correct	0 ms	212 KB	Output is correct

Subtask #2
45.0 / 45.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	212 KB	Output is correct
2	Correct	1 ms	212 KB	Output is correct
3	Correct	1 ms	212 KB	Output is correct
4	Correct	0 ms	212 KB	Output is correct
5	Correct	1 ms	212 KB	Output is correct
6	Correct	1 ms	212 KB	Output is correct
7	Correct	1 ms	212 KB	Output is correct
8	Correct	1 ms	212 KB	Output is correct
9	Correct	1 ms	212 KB	Output is correct
10	Correct	0 ms	212 KB	Output is correct
11	Correct	0 ms	212 KB	Output is correct
12	Correct	0 ms	212 KB	Output is correct
13	Correct	0 ms	212 KB	Output is correct
14	Correct	1 ms	212 KB	Output is correct
15	Correct	0 ms	212 KB	Output is correct
16	Correct	0 ms	212 KB	Output is correct
17	Correct	0 ms	212 KB	Output is correct
18	Correct	0 ms	212 KB	Output is correct
19	Correct	0 ms	212 KB	Output is correct
20	Correct	0 ms	212 KB	Output is correct
21	Correct	0 ms	212 KB	Output is correct
22	Correct	1 ms	340 KB	Output is correct
23	Correct	1 ms	340 KB	Output is correct
24	Correct	1 ms	340 KB	Output is correct
25	Correct	1 ms	340 KB	Output is correct
26	Correct	1 ms	340 KB	Output is correct
27	Correct	2 ms	340 KB	Output is correct
28	Correct	1 ms	340 KB	Output is correct
29	Correct	1 ms	340 KB	Output is correct
30	Correct	0 ms	212 KB	Output is correct
31	Correct	1 ms	340 KB	Output is correct
32	Correct	1 ms	212 KB	Output is correct
33	Correct	0 ms	212 KB	Output is correct
34	Correct	0 ms	212 KB	Output is correct
35	Correct	0 ms	212 KB	Output is correct
36	Correct	1 ms	212 KB	Output is correct
37	Correct	1 ms	340 KB	Output is correct
38	Correct	1 ms	340 KB	Output is correct
39	Correct	0 ms	212 KB	Output is correct
40	Correct	0 ms	212 KB	Output is correct
41	Correct	0 ms	212 KB	Output is correct
42	Correct	1 ms	256 KB	Output is correct
43	Correct	1 ms	340 KB	Output is correct
44	Correct	0 ms	212 KB	Output is correct
45	Correct	1 ms	340 KB	Output is correct
46	Correct	1 ms	340 KB	Output is correct
47	Correct	0 ms	212 KB	Output is correct
48	Correct	1 ms	212 KB	Output is correct
49	Correct	1 ms	340 KB	Output is correct
50	Correct	1 ms	212 KB	Output is correct
51	Correct	0 ms	212 KB	Output is correct
52	Correct	1 ms	340 KB	Output is correct
53	Correct	1 ms	340 KB	Output is correct
54	Correct	1 ms	212 KB	Output is correct
55	Correct	1 ms	340 KB	Output is correct
56	Correct	0 ms	212 KB	Output is correct
57	Correct	1 ms	340 KB	Output is correct
58	Correct	1 ms	468 KB	Output is correct

Subtask #3
37.0 / 37.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	212 KB	Output is correct
2	Correct	1 ms	212 KB	Output is correct
3	Correct	1 ms	212 KB	Output is correct
4	Correct	0 ms	212 KB	Output is correct
5	Correct	1 ms	212 KB	Output is correct
6	Correct	1 ms	212 KB	Output is correct
7	Correct	1 ms	212 KB	Output is correct
8	Correct	1 ms	212 KB	Output is correct
9	Correct	1 ms	212 KB	Output is correct
10	Correct	0 ms	212 KB	Output is correct
11	Correct	0 ms	212 KB	Output is correct
12	Correct	0 ms	212 KB	Output is correct
13	Correct	0 ms	212 KB	Output is correct
14	Correct	1 ms	212 KB	Output is correct
15	Correct	0 ms	212 KB	Output is correct
16	Correct	0 ms	212 KB	Output is correct
17	Correct	0 ms	212 KB	Output is correct
18	Correct	0 ms	212 KB	Output is correct
19	Correct	0 ms	212 KB	Output is correct
20	Correct	0 ms	212 KB	Output is correct
21	Correct	0 ms	212 KB	Output is correct
22	Correct	1 ms	340 KB	Output is correct
23	Correct	1 ms	340 KB	Output is correct
24	Correct	1 ms	340 KB	Output is correct
25	Correct	1 ms	340 KB	Output is correct
26	Correct	1 ms	340 KB	Output is correct
27	Correct	2 ms	340 KB	Output is correct
28	Correct	1 ms	340 KB	Output is correct
29	Correct	1 ms	340 KB	Output is correct
30	Correct	0 ms	212 KB	Output is correct
31	Correct	1 ms	340 KB	Output is correct
32	Correct	1 ms	212 KB	Output is correct
33	Correct	0 ms	212 KB	Output is correct
34	Correct	0 ms	212 KB	Output is correct
35	Correct	0 ms	212 KB	Output is correct
36	Correct	1 ms	212 KB	Output is correct
37	Correct	1 ms	340 KB	Output is correct
38	Correct	1 ms	340 KB	Output is correct
39	Correct	0 ms	212 KB	Output is correct
40	Correct	0 ms	212 KB	Output is correct
41	Correct	0 ms	212 KB	Output is correct
42	Correct	1 ms	256 KB	Output is correct
43	Correct	1 ms	340 KB	Output is correct
44	Correct	0 ms	212 KB	Output is correct
45	Correct	1 ms	340 KB	Output is correct
46	Correct	1 ms	340 KB	Output is correct
47	Correct	0 ms	212 KB	Output is correct
48	Correct	1 ms	212 KB	Output is correct
49	Correct	1 ms	340 KB	Output is correct
50	Correct	1 ms	212 KB	Output is correct
51	Correct	0 ms	212 KB	Output is correct
52	Correct	1 ms	340 KB	Output is correct
53	Correct	1 ms	340 KB	Output is correct
54	Correct	1 ms	212 KB	Output is correct
55	Correct	1 ms	340 KB	Output is correct
56	Correct	0 ms	212 KB	Output is correct
57	Correct	1 ms	340 KB	Output is correct
58	Correct	1 ms	468 KB	Output is correct
59	Correct	333 ms	30440 KB	Output is correct
60	Correct	434 ms	33996 KB	Output is correct
61	Correct	0 ms	212 KB	Output is correct
62	Correct	1 ms	212 KB	Output is correct
63	Correct	287 ms	27404 KB	Output is correct
64	Correct	2 ms	852 KB	Output is correct
65	Correct	9 ms	2888 KB	Output is correct
66	Correct	135 ms	21516 KB	Output is correct
67	Correct	542 ms	46428 KB	Output is correct
68	Correct	536 ms	47140 KB	Output is correct
69	Correct	5 ms	1364 KB	Output is correct
70	Correct	74 ms	11732 KB	Output is correct
71	Correct	267 ms	36936 KB	Output is correct
72	Correct	285 ms	36144 KB	Output is correct
73	Correct	120 ms	9408 KB	Output is correct
74	Correct	452 ms	32844 KB	Output is correct
75	Correct	26 ms	4248 KB	Output is correct
76	Correct	308 ms	36580 KB	Output is correct
77	Correct	290 ms	37004 KB	Output is correct
78	Correct	34 ms	4608 KB	Output is correct
79	Correct	497 ms	44120 KB	Output is correct
80	Correct	2 ms	596 KB	Output is correct
81	Correct	100 ms	11992 KB	Output is correct
82	Correct	384 ms	34860 KB	Output is correct
83	Correct	416 ms	32880 KB	Output is correct
84	Correct	443 ms	32864 KB	Output is correct
85	Correct	436 ms	32844 KB	Output is correct
86	Correct	399 ms	33948 KB	Output is correct
87	Correct	427 ms	33868 KB	Output is correct

Submission #583425

Compilation message

Subtask #1 18.0 / 18.0

Subtask #2 45.0 / 45.0

Subtask #3 37.0 / 37.0

Subtask #1
18.0 / 18.0

Subtask #2
45.0 / 45.0

Subtask #3
37.0 / 37.0