Submission #298510

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
298510	2020-09-13T03:38:11 Z	jbroeksteeg	Network (BOI15_net)	C++14	100 / 100	853 ms	47728 KB

#include <iostream>
#include <climits>
#include <numeric>
#include <cassert>
#include <algorithm>
#include <queue>
#include <map>
#include <stack>
#include <set>
#include <vector>
#include <array>
#include <memory>

#define IN(a,b) (a.find(b) != a.end())
#define p(a,b) make_pair(a,b)
#define readVec(a) for (int __i = 0; __i<(int)a.size();__i++){cin>>a[__i];}

// jimjam

template<typename T>
void pMin(T &a, T b) {if (b<a){a=b;}}
template<typename T>
void pMax(T &a, T b) {if (b>a){a=b;}}
template<typename T>
std::ostream& operator<<(std::ostream& os, const std::vector<T>& c);
template<typename A, typename B>
std::ostream& operator<<(std::ostream& os, const std::pair<A,B>& c) {std::cout << "(" << c.first << ", " << c.second << ")";return os;}
template<typename T>
std::ostream& operator<<(std::ostream& os, const std::vector<T>& c) {
	if (c.size() == 0) {os << "{}"; return os;}
	os << "{" << c[0];
	for (int i = 1; i < (int)c.size(); i++) {os <<", "<<c[i];}
	os << "}";
	return os;
}

const int inf = 2e9;
#define MAXN 500001

using namespace std;

vector<int> adj[MAXN];
vector<int> leaves;

void dfs(int c, int p=-1) {

	if (adj[c].size()==1) {
		leaves.push_back(c);
	}
	for (int i: adj[c]) {
		if (i!=p) {
			dfs(i,c);
		}
	}
}
int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);

	
	int n; cin >> n;
	for (int i = 0; i < n-1; i++) {
		int a, b; cin >> a >> b;
		adj[a].push_back(b);
		adj[b].push_back(a);
	}
	for (int i = 1; i <= n; i++) {
		if (adj[i].size()>1) {
			dfs(i);
			break;
		}
	}
//	cout << leaves.size()/2 + leaves.size()%2 << "\n";
	int cnt=0;
	while (cnt<leaves.size()) {
		if (cnt+1==leaves.size()) {
//			cout << leaves[cnt] << " 1\n";
			cnt++;
		} else {
//			cout << leaves[cnt] << " " << leaves[cnt+1] << "\n";
			cnt+=2;
		}
		
	}
	cout << leaves.size()/2 + leaves.size()%2 << endl;
	for (int i = 0; i < leaves.size()/2+leaves.size()%2; i++) {
		cout << leaves[i] << " " << leaves[i + leaves.size()/2] << endl;
		//if (other<i) break;
	}
	return 0;
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:75:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   75 |  while (cnt<leaves.size()) {
      |         ~~~^~~~~~~~~~~~~~
net.cpp:76:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   76 |   if (cnt+1==leaves.size()) {
      |       ~~~~~^~~~~~~~~~~~~~~
net.cpp:86:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   86 |  for (int i = 0; i < leaves.size()/2+leaves.size()%2; i++) {
      |                  ~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	8 ms	12032 KB	Output is correct
2	Correct	8 ms	12032 KB	Output is correct
3	Correct	8 ms	12160 KB	Output is correct
4	Correct	8 ms	12032 KB	Output is correct
5	Correct	8 ms	12032 KB	Output is correct
6	Correct	8 ms	12032 KB	Output is correct
7	Correct	8 ms	12032 KB	Output is correct
8	Correct	8 ms	12032 KB	Output is correct
9	Correct	8 ms	12032 KB	Output is correct
10	Correct	8 ms	12032 KB	Output is correct
11	Correct	8 ms	12032 KB	Output is correct
12	Correct	8 ms	12032 KB	Output is correct
13	Correct	9 ms	12032 KB	Output is correct
14	Correct	8 ms	12032 KB	Output is correct
15	Correct	8 ms	12032 KB	Output is correct
16	Correct	8 ms	12032 KB	Output is correct
17	Correct	8 ms	12032 KB	Output is correct
18	Correct	8 ms	12032 KB	Output is correct
19	Correct	8 ms	12032 KB	Output is correct
20	Correct	8 ms	12032 KB	Output is correct

Subtask #2
45.0 / 45.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	8 ms	12032 KB	Output is correct
2	Correct	8 ms	12032 KB	Output is correct
3	Correct	8 ms	12160 KB	Output is correct
4	Correct	8 ms	12032 KB	Output is correct
5	Correct	8 ms	12032 KB	Output is correct
6	Correct	8 ms	12032 KB	Output is correct
7	Correct	8 ms	12032 KB	Output is correct
8	Correct	8 ms	12032 KB	Output is correct
9	Correct	8 ms	12032 KB	Output is correct
10	Correct	8 ms	12032 KB	Output is correct
11	Correct	8 ms	12032 KB	Output is correct
12	Correct	8 ms	12032 KB	Output is correct
13	Correct	9 ms	12032 KB	Output is correct
14	Correct	8 ms	12032 KB	Output is correct
15	Correct	8 ms	12032 KB	Output is correct
16	Correct	8 ms	12032 KB	Output is correct
17	Correct	8 ms	12032 KB	Output is correct
18	Correct	8 ms	12032 KB	Output is correct
19	Correct	8 ms	12032 KB	Output is correct
20	Correct	8 ms	12032 KB	Output is correct
21	Correct	8 ms	12032 KB	Output is correct
22	Correct	11 ms	12160 KB	Output is correct
23	Correct	11 ms	12160 KB	Output is correct
24	Correct	11 ms	12160 KB	Output is correct
25	Correct	10 ms	12160 KB	Output is correct
26	Correct	10 ms	12160 KB	Output is correct
27	Correct	11 ms	12288 KB	Output is correct
28	Correct	12 ms	12160 KB	Output is correct
29	Correct	10 ms	12160 KB	Output is correct
30	Correct	8 ms	12032 KB	Output is correct
31	Correct	11 ms	12160 KB	Output is correct
32	Correct	9 ms	12032 KB	Output is correct
33	Correct	8 ms	12032 KB	Output is correct
34	Correct	8 ms	12032 KB	Output is correct
35	Correct	9 ms	12160 KB	Output is correct
36	Correct	9 ms	12032 KB	Output is correct
37	Correct	9 ms	12288 KB	Output is correct
38	Correct	9 ms	12160 KB	Output is correct
39	Correct	8 ms	12032 KB	Output is correct
40	Correct	9 ms	12032 KB	Output is correct
41	Correct	9 ms	12032 KB	Output is correct
42	Correct	9 ms	12032 KB	Output is correct
43	Correct	10 ms	12160 KB	Output is correct
44	Correct	8 ms	12032 KB	Output is correct
45	Correct	9 ms	12032 KB	Output is correct
46	Correct	9 ms	12160 KB	Output is correct
47	Correct	8 ms	12032 KB	Output is correct
48	Correct	9 ms	12032 KB	Output is correct
49	Correct	10 ms	12160 KB	Output is correct
50	Correct	8 ms	12032 KB	Output is correct
51	Correct	8 ms	12032 KB	Output is correct
52	Correct	8 ms	12032 KB	Output is correct
53	Correct	9 ms	12160 KB	Output is correct
54	Correct	8 ms	12032 KB	Output is correct
55	Correct	9 ms	12032 KB	Output is correct
56	Correct	9 ms	12032 KB	Output is correct
57	Correct	9 ms	12160 KB	Output is correct
58	Correct	11 ms	12160 KB	Output is correct

Subtask #3
37.0 / 37.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	8 ms	12032 KB	Output is correct
2	Correct	8 ms	12032 KB	Output is correct
3	Correct	8 ms	12160 KB	Output is correct
4	Correct	8 ms	12032 KB	Output is correct
5	Correct	8 ms	12032 KB	Output is correct
6	Correct	8 ms	12032 KB	Output is correct
7	Correct	8 ms	12032 KB	Output is correct
8	Correct	8 ms	12032 KB	Output is correct
9	Correct	8 ms	12032 KB	Output is correct
10	Correct	8 ms	12032 KB	Output is correct
11	Correct	8 ms	12032 KB	Output is correct
12	Correct	8 ms	12032 KB	Output is correct
13	Correct	9 ms	12032 KB	Output is correct
14	Correct	8 ms	12032 KB	Output is correct
15	Correct	8 ms	12032 KB	Output is correct
16	Correct	8 ms	12032 KB	Output is correct
17	Correct	8 ms	12032 KB	Output is correct
18	Correct	8 ms	12032 KB	Output is correct
19	Correct	8 ms	12032 KB	Output is correct
20	Correct	8 ms	12032 KB	Output is correct
21	Correct	8 ms	12032 KB	Output is correct
22	Correct	11 ms	12160 KB	Output is correct
23	Correct	11 ms	12160 KB	Output is correct
24	Correct	11 ms	12160 KB	Output is correct
25	Correct	10 ms	12160 KB	Output is correct
26	Correct	10 ms	12160 KB	Output is correct
27	Correct	11 ms	12288 KB	Output is correct
28	Correct	12 ms	12160 KB	Output is correct
29	Correct	10 ms	12160 KB	Output is correct
30	Correct	8 ms	12032 KB	Output is correct
31	Correct	11 ms	12160 KB	Output is correct
32	Correct	9 ms	12032 KB	Output is correct
33	Correct	8 ms	12032 KB	Output is correct
34	Correct	8 ms	12032 KB	Output is correct
35	Correct	9 ms	12160 KB	Output is correct
36	Correct	9 ms	12032 KB	Output is correct
37	Correct	9 ms	12288 KB	Output is correct
38	Correct	9 ms	12160 KB	Output is correct
39	Correct	8 ms	12032 KB	Output is correct
40	Correct	9 ms	12032 KB	Output is correct
41	Correct	9 ms	12032 KB	Output is correct
42	Correct	9 ms	12032 KB	Output is correct
43	Correct	10 ms	12160 KB	Output is correct
44	Correct	8 ms	12032 KB	Output is correct
45	Correct	9 ms	12032 KB	Output is correct
46	Correct	9 ms	12160 KB	Output is correct
47	Correct	8 ms	12032 KB	Output is correct
48	Correct	9 ms	12032 KB	Output is correct
49	Correct	10 ms	12160 KB	Output is correct
50	Correct	8 ms	12032 KB	Output is correct
51	Correct	8 ms	12032 KB	Output is correct
52	Correct	8 ms	12032 KB	Output is correct
53	Correct	9 ms	12160 KB	Output is correct
54	Correct	8 ms	12032 KB	Output is correct
55	Correct	9 ms	12032 KB	Output is correct
56	Correct	9 ms	12032 KB	Output is correct
57	Correct	9 ms	12160 KB	Output is correct
58	Correct	11 ms	12160 KB	Output is correct
59	Correct	714 ms	36328 KB	Output is correct
60	Correct	812 ms	39148 KB	Output is correct
61	Correct	8 ms	12032 KB	Output is correct
62	Correct	8 ms	12032 KB	Output is correct
63	Correct	683 ms	33652 KB	Output is correct
64	Correct	10 ms	12544 KB	Output is correct
65	Correct	21 ms	13952 KB	Output is correct
66	Correct	167 ms	27892 KB	Output is correct
67	Correct	522 ms	46968 KB	Output is correct
68	Correct	559 ms	47728 KB	Output is correct
69	Correct	34 ms	12928 KB	Output is correct
70	Correct	255 ms	21348 KB	Output is correct
71	Correct	853 ms	42248 KB	Output is correct
72	Correct	826 ms	40932 KB	Output is correct
73	Correct	177 ms	19188 KB	Output is correct
74	Correct	752 ms	37868 KB	Output is correct
75	Correct	86 ms	15480 KB	Output is correct
76	Correct	843 ms	41720 KB	Output is correct
77	Correct	843 ms	41688 KB	Output is correct
78	Correct	50 ms	15736 KB	Output is correct
79	Correct	508 ms	45176 KB	Output is correct
80	Correct	13 ms	12288 KB	Output is correct
81	Correct	252 ms	21400 KB	Output is correct
82	Correct	800 ms	39652 KB	Output is correct
83	Correct	742 ms	37876 KB	Output is correct
84	Correct	740 ms	37736 KB	Output is correct
85	Correct	738 ms	37800 KB	Output is correct
86	Correct	820 ms	38888 KB	Output is correct
87	Correct	806 ms	38888 KB	Output is correct

Submission #298510

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