Submission #1008743

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
1008743	2024-06-26T17:21:26 Z	ByeWorld	Network (BOI15_net)	C++14	63 / 100	2 ms	612 KB

#include <bits/stdc++.h>
#pragma GCC optimize("O3", "unroll-loops")
#define ll long long
#define int long long
#define pb push_back
#define fi first
#define se second
#define lf (id<<1)
#define rg ((id<<1)|1)
#define md ((l+r)>>1)
#define ld long double
using namespace std;
typedef pair<int,int> pii;
typedef pair<pii, int> ipii;
const int MAXN = 3e3+10;
const int INF = 1e18+10;
const int LOG = 19;
const int MOD = 1e9+7;
const int SQRT = 450;
const vector<int> NOL = {};
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const vector<int> dx = {1, -1, 0, 0};
const vector<int> dy = {0, 0, 1, -1};

int n;
vector <int> adj[MAXN];
vector <pii> ans;
vector <int> leaf;
int root;

void dfs(int nw, int par){
	if(adj[nw].size()==1) leaf.pb(nw);
	for(auto nx : adj[nw]){
		if(nx==par) continue;
		dfs(nx, nw);
	}
}
signed main(){
	// ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	cin >> n;
	for(int i=1; i<=n-1; i++){
		int x, y; cin >> x >> y;
		adj[x].pb(y); adj[y].pb(x);
	}
	for(int i=1; i<=n; i++){
		if(adj[i].size()!=1) root = i;
	}

	dfs(root, 0);
	int siz = leaf.size();
	cout << (leaf.size()+1)/2 << '\n';
	for(int i=0; i<(siz+1)/2; i++) 
		cout << leaf[i] << ' ' << leaf[i+siz/2] << '\n';
}

Subtask #1
18.0 / 18.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	600 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	0 ms	604 KB	Output is correct
4	Correct	0 ms	344 KB	Output is correct
5	Correct	0 ms	348 KB	Output is correct
6	Correct	0 ms	348 KB	Output is correct
7	Correct	1 ms	344 KB	Output is correct
8	Correct	0 ms	604 KB	Output is correct
9	Correct	0 ms	348 KB	Output is correct
10	Correct	0 ms	344 KB	Output is correct
11	Correct	0 ms	344 KB	Output is correct
12	Correct	0 ms	348 KB	Output is correct
13	Correct	0 ms	348 KB	Output is correct
14	Correct	0 ms	344 KB	Output is correct
15	Correct	0 ms	348 KB	Output is correct
16	Correct	1 ms	344 KB	Output is correct
17	Correct	1 ms	344 KB	Output is correct
18	Correct	0 ms	344 KB	Output is correct
19	Correct	1 ms	344 KB	Output is correct
20	Correct	0 ms	348 KB	Output is correct

Subtask #2
45.0 / 45.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	600 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	0 ms	604 KB	Output is correct
4	Correct	0 ms	344 KB	Output is correct
5	Correct	0 ms	348 KB	Output is correct
6	Correct	0 ms	348 KB	Output is correct
7	Correct	1 ms	344 KB	Output is correct
8	Correct	0 ms	604 KB	Output is correct
9	Correct	0 ms	348 KB	Output is correct
10	Correct	0 ms	344 KB	Output is correct
11	Correct	0 ms	344 KB	Output is correct
12	Correct	0 ms	348 KB	Output is correct
13	Correct	0 ms	348 KB	Output is correct
14	Correct	0 ms	344 KB	Output is correct
15	Correct	0 ms	348 KB	Output is correct
16	Correct	1 ms	344 KB	Output is correct
17	Correct	1 ms	344 KB	Output is correct
18	Correct	0 ms	344 KB	Output is correct
19	Correct	1 ms	344 KB	Output is correct
20	Correct	0 ms	348 KB	Output is correct
21	Correct	0 ms	348 KB	Output is correct
22	Correct	1 ms	612 KB	Output is correct
23	Correct	1 ms	604 KB	Output is correct
24	Correct	1 ms	604 KB	Output is correct
25	Correct	1 ms	604 KB	Output is correct
26	Correct	1 ms	348 KB	Output is correct
27	Correct	1 ms	604 KB	Output is correct
28	Correct	1 ms	604 KB	Output is correct
29	Correct	2 ms	604 KB	Output is correct
30	Correct	1 ms	348 KB	Output is correct
31	Correct	1 ms	604 KB	Output is correct
32	Correct	0 ms	348 KB	Output is correct
33	Correct	0 ms	348 KB	Output is correct
34	Correct	1 ms	348 KB	Output is correct
35	Correct	0 ms	348 KB	Output is correct
36	Correct	0 ms	344 KB	Output is correct
37	Correct	1 ms	344 KB	Output is correct
38	Correct	1 ms	348 KB	Output is correct
39	Correct	0 ms	508 KB	Output is correct
40	Correct	0 ms	348 KB	Output is correct
41	Correct	0 ms	348 KB	Output is correct
42	Correct	1 ms	348 KB	Output is correct
43	Correct	1 ms	348 KB	Output is correct
44	Correct	0 ms	348 KB	Output is correct
45	Correct	1 ms	348 KB	Output is correct
46	Correct	1 ms	348 KB	Output is correct
47	Correct	1 ms	348 KB	Output is correct
48	Correct	1 ms	344 KB	Output is correct
49	Correct	1 ms	348 KB	Output is correct
50	Correct	0 ms	348 KB	Output is correct
51	Correct	0 ms	504 KB	Output is correct
52	Correct	1 ms	348 KB	Output is correct
53	Correct	1 ms	348 KB	Output is correct
54	Correct	0 ms	348 KB	Output is correct
55	Correct	1 ms	348 KB	Output is correct
56	Correct	0 ms	348 KB	Output is correct
57	Correct	0 ms	348 KB	Output is correct
58	Correct	1 ms	600 KB	Output is correct

Subtask #3
0 / 37.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	600 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	0 ms	604 KB	Output is correct
4	Correct	0 ms	344 KB	Output is correct
5	Correct	0 ms	348 KB	Output is correct
6	Correct	0 ms	348 KB	Output is correct
7	Correct	1 ms	344 KB	Output is correct
8	Correct	0 ms	604 KB	Output is correct
9	Correct	0 ms	348 KB	Output is correct
10	Correct	0 ms	344 KB	Output is correct
11	Correct	0 ms	344 KB	Output is correct
12	Correct	0 ms	348 KB	Output is correct
13	Correct	0 ms	348 KB	Output is correct
14	Correct	0 ms	344 KB	Output is correct
15	Correct	0 ms	348 KB	Output is correct
16	Correct	1 ms	344 KB	Output is correct
17	Correct	1 ms	344 KB	Output is correct
18	Correct	0 ms	344 KB	Output is correct
19	Correct	1 ms	344 KB	Output is correct
20	Correct	0 ms	348 KB	Output is correct
21	Correct	0 ms	348 KB	Output is correct
22	Correct	1 ms	612 KB	Output is correct
23	Correct	1 ms	604 KB	Output is correct
24	Correct	1 ms	604 KB	Output is correct
25	Correct	1 ms	604 KB	Output is correct
26	Correct	1 ms	348 KB	Output is correct
27	Correct	1 ms	604 KB	Output is correct
28	Correct	1 ms	604 KB	Output is correct
29	Correct	2 ms	604 KB	Output is correct
30	Correct	1 ms	348 KB	Output is correct
31	Correct	1 ms	604 KB	Output is correct
32	Correct	0 ms	348 KB	Output is correct
33	Correct	0 ms	348 KB	Output is correct
34	Correct	1 ms	348 KB	Output is correct
35	Correct	0 ms	348 KB	Output is correct
36	Correct	0 ms	344 KB	Output is correct
37	Correct	1 ms	344 KB	Output is correct
38	Correct	1 ms	348 KB	Output is correct
39	Correct	0 ms	508 KB	Output is correct
40	Correct	0 ms	348 KB	Output is correct
41	Correct	0 ms	348 KB	Output is correct
42	Correct	1 ms	348 KB	Output is correct
43	Correct	1 ms	348 KB	Output is correct
44	Correct	0 ms	348 KB	Output is correct
45	Correct	1 ms	348 KB	Output is correct
46	Correct	1 ms	348 KB	Output is correct
47	Correct	1 ms	348 KB	Output is correct
48	Correct	1 ms	344 KB	Output is correct
49	Correct	1 ms	348 KB	Output is correct
50	Correct	0 ms	348 KB	Output is correct
51	Correct	0 ms	504 KB	Output is correct
52	Correct	1 ms	348 KB	Output is correct
53	Correct	1 ms	348 KB	Output is correct
54	Correct	0 ms	348 KB	Output is correct
55	Correct	1 ms	348 KB	Output is correct
56	Correct	0 ms	348 KB	Output is correct
57	Correct	0 ms	348 KB	Output is correct
58	Correct	1 ms	600 KB	Output is correct
59	Runtime error	1 ms	600 KB	Execution killed with signal 11
60	Halted	0 ms	0 KB	-

Submission #1008743

Compilation message

Subtask #1 18.0 / 18.0

Subtask #2 45.0 / 45.0

Subtask #3 0 / 37.0

Subtask #1
18.0 / 18.0

Subtask #2
45.0 / 45.0

Subtask #3
0 / 37.0