답안 #95951 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
95951	2019-02-04T16:56:20 Z	caesar2001	Network (BOI15_net)	C++14	100 / 100	909 ms	90220 KB

#include <bits/stdc++.h>
#define ll long long
#define lsb(x) (x & -x)

using namespace std;

void dfs(int node, vector<int> &dad, const vector<vector<int>> &g, vector<int> &leaves) {
    bool flag = 0;
    for(auto it : g[node]) {
        if(it != dad[node]) {
            dad[it] = node;
            dfs(it, dad, g, leaves);

            leaves[node] += leaves[it];
            flag = 1;
        }
    }

    if(!flag)
        leaves[node] = 1;
}

void getleaves(int node, int dad, const vector<vector<int>> &g, vector<int> &v) {
    bool flag = 0;
    for(auto it : g[node]) {
        if(it == dad)
            continue;

        getleaves(it, node, g, v);
        flag = 1;
    }

    if(!flag)
        v.push_back(node);
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    //freopen("a.in", "r", stdin);
    //freopen("a.out", "w", stdout);

    int n;
    cin >> n;
    vector<vector<int>> g(n + 1);
    int start = 1;
    for(int i = 1; i < n; i ++) {
        int x, y;
        cin >> x >> y;
        g[x].push_back(y);
        g[y].push_back(x);
    }
    for(int i = 1; i <= n; i ++)
        if(g[i].size() > 1)
            start = i;

    vector<int> leaves(n + 1, 0);
    vector<int> dad(n + 1, 0);
    dfs(start, dad, g, leaves);

    int centroid = 0;
    for(int i = 1; i <= n; i ++) {
        int lim = leaves[start] / 2;
        bool isok = 1;
        for(auto it : g[i]) {
            if(dad[i] == it && leaves[start] - leaves[i] > lim)
                isok = 0;
            else if(dad[i] != it && leaves[it] > lim)
                isok = 0;
        }

        if(isok && g[i].size() > 1) /// a doua conditie de aici???
            centroid = i;
    }
    assert(centroid != 0);

    priority_queue<pair<int, int>> pq;
    vector<vector<int>> listofleaves(n + 1);
    for(auto it : g[centroid]) {
        getleaves(it, centroid, g, listofleaves[it]);
        pq.push({listofleaves[it].size(), it});
    }

    vector<pair<int, int>> sol;
    while(pq.size() >= 2) {
        auto a = pq.top().second;
        pq.pop();
        auto b = pq.top().second;
        pq.pop();

        sol.push_back({listofleaves[a].back(), listofleaves[b].back()}); /// to change
        listofleaves[a].pop_back();
        listofleaves[b].pop_back();

        if(listofleaves[a].size() > 0)
            pq.push({listofleaves[a].size(), a});
        if(listofleaves[b].size() > 0)
            pq.push({listofleaves[b].size(), b});
    }

    if(pq.size() == 1)
        sol.push_back({centroid, listofleaves[pq.top().second].back()});

    cout << sol.size() << "\n";
    for(auto it : sol)
       cout << it.first << " " << it.second << "\n";

    return 0;
}

Subtask #1
18.0 / 18.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	376 KB	Output is correct
2	Correct	2 ms	376 KB	Output is correct
3	Correct	0 ms	376 KB	Output is correct
4	Correct	2 ms	376 KB	Output is correct
5	Correct	2 ms	376 KB	Output is correct
6	Correct	2 ms	376 KB	Output is correct
7	Correct	2 ms	376 KB	Output is correct
8	Correct	2 ms	376 KB	Output is correct
9	Correct	2 ms	376 KB	Output is correct
10	Correct	2 ms	376 KB	Output is correct
11	Correct	2 ms	376 KB	Output is correct
12	Correct	2 ms	376 KB	Output is correct
13	Correct	2 ms	376 KB	Output is correct
14	Correct	2 ms	376 KB	Output is correct
15	Correct	2 ms	376 KB	Output is correct
16	Correct	2 ms	376 KB	Output is correct
17	Correct	2 ms	376 KB	Output is correct
18	Correct	2 ms	376 KB	Output is correct
19	Correct	2 ms	376 KB	Output is correct
20	Correct	2 ms	376 KB	Output is correct

Subtask #2
45.0 / 45.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	376 KB	Output is correct
2	Correct	2 ms	376 KB	Output is correct
3	Correct	0 ms	376 KB	Output is correct
4	Correct	2 ms	376 KB	Output is correct
5	Correct	2 ms	376 KB	Output is correct
6	Correct	2 ms	376 KB	Output is correct
7	Correct	2 ms	376 KB	Output is correct
8	Correct	2 ms	376 KB	Output is correct
9	Correct	2 ms	376 KB	Output is correct
10	Correct	2 ms	376 KB	Output is correct
11	Correct	2 ms	376 KB	Output is correct
12	Correct	2 ms	376 KB	Output is correct
13	Correct	2 ms	376 KB	Output is correct
14	Correct	2 ms	376 KB	Output is correct
15	Correct	2 ms	376 KB	Output is correct
16	Correct	2 ms	376 KB	Output is correct
17	Correct	2 ms	376 KB	Output is correct
18	Correct	2 ms	376 KB	Output is correct
19	Correct	2 ms	376 KB	Output is correct
20	Correct	2 ms	376 KB	Output is correct
21	Correct	2 ms	376 KB	Output is correct
22	Correct	3 ms	632 KB	Output is correct
23	Correct	2 ms	632 KB	Output is correct
24	Correct	3 ms	632 KB	Output is correct
25	Correct	2 ms	504 KB	Output is correct
26	Correct	2 ms	504 KB	Output is correct
27	Correct	2 ms	504 KB	Output is correct
28	Correct	2 ms	504 KB	Output is correct
29	Correct	2 ms	504 KB	Output is correct
30	Correct	2 ms	376 KB	Output is correct
31	Correct	2 ms	504 KB	Output is correct
32	Correct	2 ms	376 KB	Output is correct
33	Correct	2 ms	376 KB	Output is correct
34	Correct	2 ms	376 KB	Output is correct
35	Correct	2 ms	376 KB	Output is correct
36	Correct	2 ms	376 KB	Output is correct
37	Correct	3 ms	376 KB	Output is correct
38	Correct	2 ms	504 KB	Output is correct
39	Correct	2 ms	376 KB	Output is correct
40	Correct	2 ms	376 KB	Output is correct
41	Correct	2 ms	376 KB	Output is correct
42	Correct	2 ms	376 KB	Output is correct
43	Correct	2 ms	504 KB	Output is correct
44	Correct	2 ms	376 KB	Output is correct
45	Correct	2 ms	376 KB	Output is correct
46	Correct	2 ms	504 KB	Output is correct
47	Correct	2 ms	376 KB	Output is correct
48	Correct	2 ms	376 KB	Output is correct
49	Correct	2 ms	504 KB	Output is correct
50	Correct	2 ms	424 KB	Output is correct
51	Correct	2 ms	376 KB	Output is correct
52	Correct	2 ms	376 KB	Output is correct
53	Correct	2 ms	504 KB	Output is correct
54	Correct	2 ms	376 KB	Output is correct
55	Correct	2 ms	376 KB	Output is correct
56	Correct	2 ms	376 KB	Output is correct
57	Correct	2 ms	376 KB	Output is correct
58	Correct	3 ms	504 KB	Output is correct

Subtask #3
37.0 / 37.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	376 KB	Output is correct
2	Correct	2 ms	376 KB	Output is correct
3	Correct	0 ms	376 KB	Output is correct
4	Correct	2 ms	376 KB	Output is correct
5	Correct	2 ms	376 KB	Output is correct
6	Correct	2 ms	376 KB	Output is correct
7	Correct	2 ms	376 KB	Output is correct
8	Correct	2 ms	376 KB	Output is correct
9	Correct	2 ms	376 KB	Output is correct
10	Correct	2 ms	376 KB	Output is correct
11	Correct	2 ms	376 KB	Output is correct
12	Correct	2 ms	376 KB	Output is correct
13	Correct	2 ms	376 KB	Output is correct
14	Correct	2 ms	376 KB	Output is correct
15	Correct	2 ms	376 KB	Output is correct
16	Correct	2 ms	376 KB	Output is correct
17	Correct	2 ms	376 KB	Output is correct
18	Correct	2 ms	376 KB	Output is correct
19	Correct	2 ms	376 KB	Output is correct
20	Correct	2 ms	376 KB	Output is correct
21	Correct	2 ms	376 KB	Output is correct
22	Correct	3 ms	632 KB	Output is correct
23	Correct	2 ms	632 KB	Output is correct
24	Correct	3 ms	632 KB	Output is correct
25	Correct	2 ms	504 KB	Output is correct
26	Correct	2 ms	504 KB	Output is correct
27	Correct	2 ms	504 KB	Output is correct
28	Correct	2 ms	504 KB	Output is correct
29	Correct	2 ms	504 KB	Output is correct
30	Correct	2 ms	376 KB	Output is correct
31	Correct	2 ms	504 KB	Output is correct
32	Correct	2 ms	376 KB	Output is correct
33	Correct	2 ms	376 KB	Output is correct
34	Correct	2 ms	376 KB	Output is correct
35	Correct	2 ms	376 KB	Output is correct
36	Correct	2 ms	376 KB	Output is correct
37	Correct	3 ms	376 KB	Output is correct
38	Correct	2 ms	504 KB	Output is correct
39	Correct	2 ms	376 KB	Output is correct
40	Correct	2 ms	376 KB	Output is correct
41	Correct	2 ms	376 KB	Output is correct
42	Correct	2 ms	376 KB	Output is correct
43	Correct	2 ms	504 KB	Output is correct
44	Correct	2 ms	376 KB	Output is correct
45	Correct	2 ms	376 KB	Output is correct
46	Correct	2 ms	504 KB	Output is correct
47	Correct	2 ms	376 KB	Output is correct
48	Correct	2 ms	376 KB	Output is correct
49	Correct	2 ms	504 KB	Output is correct
50	Correct	2 ms	424 KB	Output is correct
51	Correct	2 ms	376 KB	Output is correct
52	Correct	2 ms	376 KB	Output is correct
53	Correct	2 ms	504 KB	Output is correct
54	Correct	2 ms	376 KB	Output is correct
55	Correct	2 ms	376 KB	Output is correct
56	Correct	2 ms	376 KB	Output is correct
57	Correct	2 ms	376 KB	Output is correct
58	Correct	3 ms	504 KB	Output is correct
59	Correct	648 ms	48884 KB	Output is correct
60	Correct	545 ms	49648 KB	Output is correct
61	Correct	2 ms	376 KB	Output is correct
62	Correct	2 ms	376 KB	Output is correct
63	Correct	628 ms	42472 KB	Output is correct
64	Correct	4 ms	1144 KB	Output is correct
65	Correct	15 ms	3832 KB	Output is correct
66	Correct	214 ms	26232 KB	Output is correct
67	Correct	827 ms	90220 KB	Output is correct
68	Correct	897 ms	75736 KB	Output is correct
69	Correct	11 ms	2424 KB	Output is correct
70	Correct	176 ms	22816 KB	Output is correct
71	Correct	828 ms	72392 KB	Output is correct
72	Correct	768 ms	69588 KB	Output is correct
73	Correct	142 ms	13684 KB	Output is correct
74	Correct	712 ms	47924 KB	Output is correct
75	Correct	42 ms	7160 KB	Output is correct
76	Correct	709 ms	60752 KB	Output is correct
77	Correct	668 ms	61668 KB	Output is correct
78	Correct	33 ms	7032 KB	Output is correct
79	Correct	909 ms	64928 KB	Output is correct
80	Correct	4 ms	804 KB	Output is correct
81	Correct	235 ms	20896 KB	Output is correct
82	Correct	654 ms	59240 KB	Output is correct
83	Correct	713 ms	47820 KB	Output is correct
84	Correct	679 ms	48492 KB	Output is correct
85	Correct	674 ms	48300 KB	Output is correct
86	Correct	640 ms	50208 KB	Output is correct
87	Correct	647 ms	50076 KB	Output is correct

답안 #95951

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