답안 #39846 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
39846	2018-01-20T22:00:56 Z	MladenP	Network (BOI15_net)	C++14	100 / 100	826 ms	69388 KB

#include<bits/stdc++.h>
#define STIZE(x) fprintf(stderr, "STIZE%d\n", x);
#define PRINT(x) fprintf(stderr, "%s = %d\n", #x, x);
#define NL(x) printf("%c", " \n"[(x)]);
#define lld long long
#define pii pair<int,int>
#define pb push_back
#define fi first
#define se second
#define all(a) begin(a),end(a)
#define sz(a) int((a).size())
#define LINF LLONG_MAX
#define INF INT_MAX
#define EPS 1e-9
using namespace std;
#define MAXN 500010
int n, root, centroid;
int deg[MAXN];
int brlist[MAXN], cntLeaf;
bool is_leaf[MAXN];
vector<int> adj[MAXN];
int dfs1(int cur, int pret) {
    if(brlist[cur] != 0) return brlist[cur];
    if(is_leaf[cur]) return brlist[cur] = 1;
    for(auto x : adj[cur]) {
        if(x != pret) brlist[cur] += dfs1(x, cur);
    }
    return brlist[cur];
}
int dfs2(int cur, int pret) {
    int maxi = 0;
    for(auto x : adj[cur]) {
        if(!is_leaf[x] && brlist[x] >= brlist[maxi] && x != pret) maxi = x;
    }
    if(brlist[maxi] > cntLeaf-cntLeaf/2) return dfs2(maxi, cur);
    else return cur;
}
int susedi;
vector<int> lisce[MAXN];
void dfs3(int cur, int pret) {
    if(is_leaf[cur]) {
        lisce[susedi].pb(cur);
        return;
    }
    for(auto x : adj[cur]) {
        if(x != pret) dfs3(x, cur);
        if(cur == centroid) susedi++;
    }
}
priority_queue<pii> pq;
int main() {
    scanf("%d", &n);
    if(n <= 2) return printf("1\n1 %d", n), 0;
    for(int i = 0; i < n-1; i++) {
        int x, y; scanf("%d%d", &x, &y);
        adj[x].pb(y);
        adj[y].pb(x);
        deg[x]++; deg[y]++;
    }
    for(int i = 1; i <= n; i++) {
        if(deg[i] == 1) is_leaf[i] = 1, cntLeaf++;
        else root = i;
    }
    dfs1(root, 0);
    centroid = dfs2(root, 0);
    dfs3(centroid, 0);
    for(int i = 0; i < susedi; i++) {
        pq.push({sz(lisce[i]), i});
    }
    printf("%d\n", cntLeaf-cntLeaf/2);
    while(sz(pq) > 1) {
        pii vrh1 = pq.top(); pq.pop();
        pii vrh2 = pq.top(); pq.pop();
        int komp1 = vrh1.se, komp2 = vrh2.se;
        int rep1 = vrh1.fi, rep2 = vrh2.fi;
        printf("%d %d\n", lisce[komp1][--rep1], lisce[komp2][--rep2]);
        if(rep1) pq.push({rep1, komp1});
        if(rep2) pq.push({rep2, komp2});
    }
    if(pq.size() == 1) {
        int komp = pq.top().se;
        printf("%d %d\n", lisce[komp][0], centroid);
    }
    return 0;
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:52:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
                    ^
net.cpp:55:40: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         int x, y; scanf("%d%d", &x, &y);
                                        ^

Subtask #1
18.0 / 18.0

#	결과	실행 시간	메모리	Grader output
1	Correct	6 ms	29856 KB	Output is correct
2	Correct	7 ms	29856 KB	Output is correct
3	Correct	0 ms	29856 KB	Output is correct
4	Correct	7 ms	29856 KB	Output is correct
5	Correct	6 ms	29856 KB	Output is correct
6	Correct	11 ms	29856 KB	Output is correct
7	Correct	11 ms	29856 KB	Output is correct
8	Correct	3 ms	29856 KB	Output is correct
9	Correct	3 ms	29856 KB	Output is correct
10	Correct	3 ms	29856 KB	Output is correct
11	Correct	7 ms	29856 KB	Output is correct
12	Correct	7 ms	29856 KB	Output is correct
13	Correct	7 ms	29856 KB	Output is correct
14	Correct	6 ms	29856 KB	Output is correct
15	Correct	6 ms	29856 KB	Output is correct
16	Correct	4 ms	29856 KB	Output is correct
17	Correct	3 ms	29856 KB	Output is correct
18	Correct	6 ms	29856 KB	Output is correct
19	Correct	10 ms	29856 KB	Output is correct
20	Correct	6 ms	29856 KB	Output is correct

Subtask #2
45.0 / 45.0

#	결과	실행 시간	메모리	Grader output
1	Correct	6 ms	29856 KB	Output is correct
2	Correct	7 ms	29856 KB	Output is correct
3	Correct	0 ms	29856 KB	Output is correct
4	Correct	7 ms	29856 KB	Output is correct
5	Correct	6 ms	29856 KB	Output is correct
6	Correct	11 ms	29856 KB	Output is correct
7	Correct	11 ms	29856 KB	Output is correct
8	Correct	3 ms	29856 KB	Output is correct
9	Correct	3 ms	29856 KB	Output is correct
10	Correct	3 ms	29856 KB	Output is correct
11	Correct	7 ms	29856 KB	Output is correct
12	Correct	7 ms	29856 KB	Output is correct
13	Correct	7 ms	29856 KB	Output is correct
14	Correct	6 ms	29856 KB	Output is correct
15	Correct	6 ms	29856 KB	Output is correct
16	Correct	4 ms	29856 KB	Output is correct
17	Correct	3 ms	29856 KB	Output is correct
18	Correct	6 ms	29856 KB	Output is correct
19	Correct	10 ms	29856 KB	Output is correct
20	Correct	6 ms	29856 KB	Output is correct
21	Correct	14 ms	29856 KB	Output is correct
22	Correct	10 ms	29988 KB	Output is correct
23	Correct	13 ms	29988 KB	Output is correct
24	Correct	3 ms	29988 KB	Output is correct
25	Correct	10 ms	29988 KB	Output is correct
26	Correct	0 ms	29988 KB	Output is correct
27	Correct	3 ms	29988 KB	Output is correct
28	Correct	3 ms	29988 KB	Output is correct
29	Correct	6 ms	29988 KB	Output is correct
30	Correct	10 ms	29856 KB	Output is correct
31	Correct	7 ms	29988 KB	Output is correct
32	Correct	0 ms	29856 KB	Output is correct
33	Correct	0 ms	29856 KB	Output is correct
34	Correct	7 ms	29856 KB	Output is correct
35	Correct	7 ms	29856 KB	Output is correct
36	Correct	3 ms	29856 KB	Output is correct
37	Correct	13 ms	29856 KB	Output is correct
38	Correct	3 ms	29856 KB	Output is correct
39	Correct	7 ms	29856 KB	Output is correct
40	Correct	10 ms	29856 KB	Output is correct
41	Correct	5 ms	29856 KB	Output is correct
42	Correct	3 ms	29856 KB	Output is correct
43	Correct	3 ms	29988 KB	Output is correct
44	Correct	7 ms	29856 KB	Output is correct
45	Correct	0 ms	29856 KB	Output is correct
46	Correct	3 ms	29856 KB	Output is correct
47	Correct	7 ms	29856 KB	Output is correct
48	Correct	3 ms	29856 KB	Output is correct
49	Correct	7 ms	29988 KB	Output is correct
50	Correct	7 ms	29856 KB	Output is correct
51	Correct	3 ms	29856 KB	Output is correct
52	Correct	3 ms	29856 KB	Output is correct
53	Correct	3 ms	29856 KB	Output is correct
54	Correct	13 ms	29856 KB	Output is correct
55	Correct	10 ms	29856 KB	Output is correct
56	Correct	0 ms	29856 KB	Output is correct
57	Correct	3 ms	29856 KB	Output is correct
58	Correct	6 ms	29988 KB	Output is correct

Subtask #3
37.0 / 37.0

#	결과	실행 시간	메모리	Grader output
1	Correct	6 ms	29856 KB	Output is correct
2	Correct	7 ms	29856 KB	Output is correct
3	Correct	0 ms	29856 KB	Output is correct
4	Correct	7 ms	29856 KB	Output is correct
5	Correct	6 ms	29856 KB	Output is correct
6	Correct	11 ms	29856 KB	Output is correct
7	Correct	11 ms	29856 KB	Output is correct
8	Correct	3 ms	29856 KB	Output is correct
9	Correct	3 ms	29856 KB	Output is correct
10	Correct	3 ms	29856 KB	Output is correct
11	Correct	7 ms	29856 KB	Output is correct
12	Correct	7 ms	29856 KB	Output is correct
13	Correct	7 ms	29856 KB	Output is correct
14	Correct	6 ms	29856 KB	Output is correct
15	Correct	6 ms	29856 KB	Output is correct
16	Correct	4 ms	29856 KB	Output is correct
17	Correct	3 ms	29856 KB	Output is correct
18	Correct	6 ms	29856 KB	Output is correct
19	Correct	10 ms	29856 KB	Output is correct
20	Correct	6 ms	29856 KB	Output is correct
21	Correct	14 ms	29856 KB	Output is correct
22	Correct	10 ms	29988 KB	Output is correct
23	Correct	13 ms	29988 KB	Output is correct
24	Correct	3 ms	29988 KB	Output is correct
25	Correct	10 ms	29988 KB	Output is correct
26	Correct	0 ms	29988 KB	Output is correct
27	Correct	3 ms	29988 KB	Output is correct
28	Correct	3 ms	29988 KB	Output is correct
29	Correct	6 ms	29988 KB	Output is correct
30	Correct	10 ms	29856 KB	Output is correct
31	Correct	7 ms	29988 KB	Output is correct
32	Correct	0 ms	29856 KB	Output is correct
33	Correct	0 ms	29856 KB	Output is correct
34	Correct	7 ms	29856 KB	Output is correct
35	Correct	7 ms	29856 KB	Output is correct
36	Correct	3 ms	29856 KB	Output is correct
37	Correct	13 ms	29856 KB	Output is correct
38	Correct	3 ms	29856 KB	Output is correct
39	Correct	7 ms	29856 KB	Output is correct
40	Correct	10 ms	29856 KB	Output is correct
41	Correct	5 ms	29856 KB	Output is correct
42	Correct	3 ms	29856 KB	Output is correct
43	Correct	3 ms	29988 KB	Output is correct
44	Correct	7 ms	29856 KB	Output is correct
45	Correct	0 ms	29856 KB	Output is correct
46	Correct	3 ms	29856 KB	Output is correct
47	Correct	7 ms	29856 KB	Output is correct
48	Correct	3 ms	29856 KB	Output is correct
49	Correct	7 ms	29988 KB	Output is correct
50	Correct	7 ms	29856 KB	Output is correct
51	Correct	3 ms	29856 KB	Output is correct
52	Correct	3 ms	29856 KB	Output is correct
53	Correct	3 ms	29856 KB	Output is correct
54	Correct	13 ms	29856 KB	Output is correct
55	Correct	10 ms	29856 KB	Output is correct
56	Correct	0 ms	29856 KB	Output is correct
57	Correct	3 ms	29856 KB	Output is correct
58	Correct	6 ms	29988 KB	Output is correct
59	Correct	601 ms	52792 KB	Output is correct
60	Correct	632 ms	48140 KB	Output is correct
61	Correct	0 ms	29856 KB	Output is correct
62	Correct	3 ms	29856 KB	Output is correct
63	Correct	442 ms	47616 KB	Output is correct
64	Correct	6 ms	30024 KB	Output is correct
65	Correct	15 ms	31220 KB	Output is correct
66	Correct	202 ms	40616 KB	Output is correct
67	Correct	781 ms	68676 KB	Output is correct
68	Correct	826 ms	61412 KB	Output is correct
69	Correct	31 ms	31088 KB	Output is correct
70	Correct	145 ms	43428 KB	Output is correct
71	Correct	466 ms	69388 KB	Output is correct
72	Correct	474 ms	67752 KB	Output is correct
73	Correct	119 ms	34760 KB	Output is correct
74	Correct	645 ms	48004 KB	Output is correct
75	Correct	43 ms	33260 KB	Output is correct
76	Correct	502 ms	59208 KB	Output is correct
77	Correct	440 ms	59536 KB	Output is correct
78	Correct	44 ms	32380 KB	Output is correct
79	Correct	751 ms	56032 KB	Output is correct
80	Correct	3 ms	30120 KB	Output is correct
81	Correct	139 ms	40272 KB	Output is correct
82	Correct	549 ms	58260 KB	Output is correct
83	Correct	618 ms	48008 KB	Output is correct
84	Correct	588 ms	47924 KB	Output is correct
85	Correct	586 ms	48296 KB	Output is correct
86	Correct	566 ms	48492 KB	Output is correct
87	Correct	596 ms	48520 KB	Output is correct

답안 #39846

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