Submission #534478

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
534478	2022-03-08T07:53:27 Z	Yazan_Alattar	Network (BOI15_net)	C++14	0 / 100	1 ms	304 KB

net

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define F first
#define S second
#define pb push_back
#define endl "\n"
#define all(x) x.begin(), x.end()
const int M = 500007;
const ll inf = 1e18;
const ll mod = 1e9+7;
const double pi = acos(-1);
const int dx[] = {0, -1, 0, 1}, dy[] = {1, 0, -1, 0};
const int block = 320;

int n, cnt[M];
vector <int> v;

int main(){
	cin >> n;
	for(int i = 1; i < n; ++i){
		int a, b;
		cin >> a >> b;
		++cnt[a];
		++cnt[b];
	}
	for(int i = 1; i <= n; ++i) if(cnt[i] == 1) v.pb(i);
	
	cout << ((int)v.size() + 1) / 2 << endl;
	for(int i = 0; i < (int)v.size() - 1; i += 2) cout << v[i] << " " << v[i + 1] << endl;
	if((int)v.size() % 2) cout << v.back() << " " << (v.back() == 1 ? 2 : 1) << endl; 
	return 0;
}

Subtask #1

0 / 18.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	204 KB	Output is correct
2	Correct	1 ms	204 KB	Output is correct
3	Correct	1 ms	204 KB	Output is correct
4	Correct	0 ms	204 KB	Output is correct
5	Correct	1 ms	304 KB	Output is correct
6	Correct	1 ms	204 KB	Output is correct
7	Correct	1 ms	296 KB	Output is correct
8	Correct	1 ms	204 KB	Output is correct
9	Correct	0 ms	204 KB	Output is correct
10	Incorrect	1 ms	204 KB	Breaking single line is causing network to disconnect.
11	Halted	0 ms	0 KB	-

Subtask #2

0 / 45.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	204 KB	Output is correct
2	Correct	1 ms	204 KB	Output is correct
3	Correct	1 ms	204 KB	Output is correct
4	Correct	0 ms	204 KB	Output is correct
5	Correct	1 ms	304 KB	Output is correct
6	Correct	1 ms	204 KB	Output is correct
7	Correct	1 ms	296 KB	Output is correct
8	Correct	1 ms	204 KB	Output is correct
9	Correct	0 ms	204 KB	Output is correct
10	Incorrect	1 ms	204 KB	Breaking single line is causing network to disconnect.
11	Halted	0 ms	0 KB	-

Subtask #3

0 / 37.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	204 KB	Output is correct
2	Correct	1 ms	204 KB	Output is correct
3	Correct	1 ms	204 KB	Output is correct
4	Correct	0 ms	204 KB	Output is correct
5	Correct	1 ms	304 KB	Output is correct
6	Correct	1 ms	204 KB	Output is correct
7	Correct	1 ms	296 KB	Output is correct
8	Correct	1 ms	204 KB	Output is correct
9	Correct	0 ms	204 KB	Output is correct
10	Incorrect	1 ms	204 KB	Breaking single line is causing network to disconnect.
11	Halted	0 ms	0 KB	-