Submission #951420

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
951420	2024-03-21T23:37:49 Z	Doncho_Bonboncho	Network (BOI15_net)	C++14	100 / 100	468 ms	63436 KB

#include <bits/stdc++.h>
using namespace std;

template< class T, class T2 > inline bool chkmin( T& a, const T2& b ){ return a > b ? a = b, 1 : 0; }
template< class T, class T2 > inline bool chkmax( T& a, const T2& b ){ return a < b ? a = b, 1 : 0; }

#ifndef LOCAL
#define cerr if( false )cerr
#endif

#define out(x) #x << " = " << x << "  "

typedef long long ll;

const int MAX_N = 1e6 + 42;
const ll mod = 1e9 + 7;

std::vector< int > v[MAX_N];
int par[MAX_N];

std::vector< int > leaves;
void dfs( int x, int p = -1 ){
	par[x] = p;
	if( v[x].size() == 1 ) leaves.push_back( x );
	for( auto j : v[x] ){
		if( j == p ) continue;
		dfs( j, x );
	}
}
int main (){

#ifndef LOCAL
	std::ios_base::sync_with_stdio( false ); std::cin.tie( NULL ); std::cout.tie( NULL );
#endif

	int n;
	std::cin >> n;

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

	std::cout << ( leaves.size() +1 ) /2 << endl;
	int add = leaves.size() >> 1;
	for( int i=0 ; i + add < leaves.size() ; i++ ){
		std::cout << leaves[i] +1 << " " << leaves[i + add] +1 << endl;
	}
	return 0;
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:52:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |  for( int i=0 ; i + add < leaves.size() ; i++ ){
      |                 ~~~~~~~~^~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	7 ms	25436 KB	Output is correct
2	Correct	7 ms	25436 KB	Output is correct
3	Correct	6 ms	25436 KB	Output is correct
4	Correct	6 ms	25436 KB	Output is correct
5	Correct	6 ms	25436 KB	Output is correct
6	Correct	7 ms	25436 KB	Output is correct
7	Correct	6 ms	25436 KB	Output is correct
8	Correct	8 ms	25436 KB	Output is correct
9	Correct	7 ms	25436 KB	Output is correct
10	Correct	6 ms	25436 KB	Output is correct
11	Correct	5 ms	25436 KB	Output is correct
12	Correct	5 ms	25436 KB	Output is correct
13	Correct	7 ms	25692 KB	Output is correct
14	Correct	6 ms	25436 KB	Output is correct
15	Correct	6 ms	25436 KB	Output is correct
16	Correct	6 ms	25436 KB	Output is correct
17	Correct	7 ms	25436 KB	Output is correct
18	Correct	6 ms	25432 KB	Output is correct
19	Correct	6 ms	25436 KB	Output is correct
20	Correct	6 ms	25436 KB	Output is correct

Subtask #2
45.0 / 45.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	7 ms	25436 KB	Output is correct
2	Correct	7 ms	25436 KB	Output is correct
3	Correct	6 ms	25436 KB	Output is correct
4	Correct	6 ms	25436 KB	Output is correct
5	Correct	6 ms	25436 KB	Output is correct
6	Correct	7 ms	25436 KB	Output is correct
7	Correct	6 ms	25436 KB	Output is correct
8	Correct	8 ms	25436 KB	Output is correct
9	Correct	7 ms	25436 KB	Output is correct
10	Correct	6 ms	25436 KB	Output is correct
11	Correct	5 ms	25436 KB	Output is correct
12	Correct	5 ms	25436 KB	Output is correct
13	Correct	7 ms	25692 KB	Output is correct
14	Correct	6 ms	25436 KB	Output is correct
15	Correct	6 ms	25436 KB	Output is correct
16	Correct	6 ms	25436 KB	Output is correct
17	Correct	7 ms	25436 KB	Output is correct
18	Correct	6 ms	25432 KB	Output is correct
19	Correct	6 ms	25436 KB	Output is correct
20	Correct	6 ms	25436 KB	Output is correct
21	Correct	6 ms	25436 KB	Output is correct
22	Correct	8 ms	25944 KB	Output is correct
23	Correct	7 ms	25692 KB	Output is correct
24	Correct	8 ms	25692 KB	Output is correct
25	Correct	7 ms	25692 KB	Output is correct
26	Correct	8 ms	25692 KB	Output is correct
27	Correct	7 ms	25692 KB	Output is correct
28	Correct	7 ms	25692 KB	Output is correct
29	Correct	6 ms	25692 KB	Output is correct
30	Correct	6 ms	25436 KB	Output is correct
31	Correct	7 ms	25688 KB	Output is correct
32	Correct	5 ms	25436 KB	Output is correct
33	Correct	5 ms	25436 KB	Output is correct
34	Correct	6 ms	25436 KB	Output is correct
35	Correct	6 ms	25436 KB	Output is correct
36	Correct	5 ms	25432 KB	Output is correct
37	Correct	6 ms	25436 KB	Output is correct
38	Correct	6 ms	25628 KB	Output is correct
39	Correct	6 ms	25436 KB	Output is correct
40	Correct	6 ms	25620 KB	Output is correct
41	Correct	6 ms	25432 KB	Output is correct
42	Correct	6 ms	25432 KB	Output is correct
43	Correct	6 ms	25432 KB	Output is correct
44	Correct	6 ms	25436 KB	Output is correct
45	Correct	6 ms	25688 KB	Output is correct
46	Correct	6 ms	25436 KB	Output is correct
47	Correct	6 ms	25436 KB	Output is correct
48	Correct	6 ms	25436 KB	Output is correct
49	Correct	6 ms	25692 KB	Output is correct
50	Correct	6 ms	25432 KB	Output is correct
51	Correct	5 ms	25436 KB	Output is correct
52	Correct	6 ms	25432 KB	Output is correct
53	Correct	7 ms	25436 KB	Output is correct
54	Correct	6 ms	25436 KB	Output is correct
55	Correct	7 ms	25436 KB	Output is correct
56	Correct	6 ms	25524 KB	Output is correct
57	Correct	6 ms	25432 KB	Output is correct
58	Correct	9 ms	25692 KB	Output is correct

Subtask #3
37.0 / 37.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	7 ms	25436 KB	Output is correct
2	Correct	7 ms	25436 KB	Output is correct
3	Correct	6 ms	25436 KB	Output is correct
4	Correct	6 ms	25436 KB	Output is correct
5	Correct	6 ms	25436 KB	Output is correct
6	Correct	7 ms	25436 KB	Output is correct
7	Correct	6 ms	25436 KB	Output is correct
8	Correct	8 ms	25436 KB	Output is correct
9	Correct	7 ms	25436 KB	Output is correct
10	Correct	6 ms	25436 KB	Output is correct
11	Correct	5 ms	25436 KB	Output is correct
12	Correct	5 ms	25436 KB	Output is correct
13	Correct	7 ms	25692 KB	Output is correct
14	Correct	6 ms	25436 KB	Output is correct
15	Correct	6 ms	25436 KB	Output is correct
16	Correct	6 ms	25436 KB	Output is correct
17	Correct	7 ms	25436 KB	Output is correct
18	Correct	6 ms	25432 KB	Output is correct
19	Correct	6 ms	25436 KB	Output is correct
20	Correct	6 ms	25436 KB	Output is correct
21	Correct	6 ms	25436 KB	Output is correct
22	Correct	8 ms	25944 KB	Output is correct
23	Correct	7 ms	25692 KB	Output is correct
24	Correct	8 ms	25692 KB	Output is correct
25	Correct	7 ms	25692 KB	Output is correct
26	Correct	8 ms	25692 KB	Output is correct
27	Correct	7 ms	25692 KB	Output is correct
28	Correct	7 ms	25692 KB	Output is correct
29	Correct	6 ms	25692 KB	Output is correct
30	Correct	6 ms	25436 KB	Output is correct
31	Correct	7 ms	25688 KB	Output is correct
32	Correct	5 ms	25436 KB	Output is correct
33	Correct	5 ms	25436 KB	Output is correct
34	Correct	6 ms	25436 KB	Output is correct
35	Correct	6 ms	25436 KB	Output is correct
36	Correct	5 ms	25432 KB	Output is correct
37	Correct	6 ms	25436 KB	Output is correct
38	Correct	6 ms	25628 KB	Output is correct
39	Correct	6 ms	25436 KB	Output is correct
40	Correct	6 ms	25620 KB	Output is correct
41	Correct	6 ms	25432 KB	Output is correct
42	Correct	6 ms	25432 KB	Output is correct
43	Correct	6 ms	25432 KB	Output is correct
44	Correct	6 ms	25436 KB	Output is correct
45	Correct	6 ms	25688 KB	Output is correct
46	Correct	6 ms	25436 KB	Output is correct
47	Correct	6 ms	25436 KB	Output is correct
48	Correct	6 ms	25436 KB	Output is correct
49	Correct	6 ms	25692 KB	Output is correct
50	Correct	6 ms	25432 KB	Output is correct
51	Correct	5 ms	25436 KB	Output is correct
52	Correct	6 ms	25432 KB	Output is correct
53	Correct	7 ms	25436 KB	Output is correct
54	Correct	6 ms	25436 KB	Output is correct
55	Correct	7 ms	25436 KB	Output is correct
56	Correct	6 ms	25524 KB	Output is correct
57	Correct	6 ms	25432 KB	Output is correct
58	Correct	9 ms	25692 KB	Output is correct
59	Correct	362 ms	51776 KB	Output is correct
60	Correct	446 ms	54468 KB	Output is correct
61	Correct	7 ms	25688 KB	Output is correct
62	Correct	7 ms	25436 KB	Output is correct
63	Correct	353 ms	49172 KB	Output is correct
64	Correct	7 ms	25944 KB	Output is correct
65	Correct	13 ms	27480 KB	Output is correct
66	Correct	69 ms	43544 KB	Output is correct
67	Correct	349 ms	62648 KB	Output is correct
68	Correct	339 ms	63436 KB	Output is correct
69	Correct	17 ms	26456 KB	Output is correct
70	Correct	128 ms	36944 KB	Output is correct
71	Correct	452 ms	57624 KB	Output is correct
72	Correct	455 ms	56380 KB	Output is correct
73	Correct	87 ms	34772 KB	Output is correct
74	Correct	439 ms	53312 KB	Output is correct
75	Correct	51 ms	30940 KB	Output is correct
76	Correct	468 ms	57204 KB	Output is correct
77	Correct	452 ms	57280 KB	Output is correct
78	Correct	30 ms	31068 KB	Output is correct
79	Correct	355 ms	60968 KB	Output is correct
80	Correct	10 ms	25688 KB	Output is correct
81	Correct	130 ms	36888 KB	Output is correct
82	Correct	439 ms	55264 KB	Output is correct
83	Correct	413 ms	53500 KB	Output is correct
84	Correct	442 ms	53444 KB	Output is correct
85	Correct	433 ms	53416 KB	Output is correct
86	Correct	465 ms	54580 KB	Output is correct
87	Correct	461 ms	54508 KB	Output is correct

Submission #951420

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