# |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
849142 |
2023-09-14T06:59:44 Z |
sandry24 |
Network (BOI15_net) |
C++17 |
|
5 ms |
12324 KB |
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> pi;
#define pb push_back
#define mp make_pair
#define f first
#define s second
vector<vi> adj(500005);
vector<bool> visited(500005);
int maxdist = 0, maxnode1 = -1, maxnode2 = -1;
void dfs(int x, int d, int &maxdist, int &maxnode){
visited[x] = 1;
if(maxdist < d){
maxdist = d;
maxnode = x;
}
for(auto i : adj[x])
if(!visited[i])
dfs(i, d+1, maxdist, maxnode);
}
void solve(){
int n;
cin >> n;
for(int i = 0; i < n-1; i++){
int a, b;
cin >> a >> b;
adj[a].pb(b);
adj[b].pb(a);
}
dfs(1, 0, maxdist, maxnode1);
visited = vector<bool>(500005);
maxdist = 0;
dfs(maxnode1, 0, maxdist, maxnode2);
vi leaves;
for(int i = 1; i <= n; i++)
if(adj[i].size() == 1 && i != maxnode1 && i != maxnode2)
leaves.pb(i);
cout << ceil((double)leaves.size()/2) + 1 << '\n';
cout << maxnode1 << ' ' << maxnode2 << '\n';
for(int i = 1; i < leaves.size(); i += 2)
cout << leaves[i-1] << ' ' << leaves[i] << '\n';
if(leaves.size() & 1)
cout << leaves.back() << ' ' << maxnode1 << '\n';
}
int main(){
//freopen("flota.in", "r", stdin);
//freopen("flota.out", "w", stdout);
//ios::sync_with_stdio(0); cin.tie(0);
int t = 1;
//cin >> t;
while(t--){
solve();
}
}
Compilation message
net.cpp: In function 'void solve()':
net.cpp:46:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
46 | for(int i = 1; i < leaves.size(); i += 2)
| ~~^~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
12124 KB |
Output is correct |
2 |
Correct |
4 ms |
12124 KB |
Output is correct |
3 |
Correct |
3 ms |
12124 KB |
Output is correct |
4 |
Correct |
4 ms |
12324 KB |
Output is correct |
5 |
Correct |
4 ms |
12280 KB |
Output is correct |
6 |
Correct |
3 ms |
12124 KB |
Output is correct |
7 |
Correct |
3 ms |
12120 KB |
Output is correct |
8 |
Correct |
3 ms |
12120 KB |
Output is correct |
9 |
Correct |
3 ms |
12120 KB |
Output is correct |
10 |
Correct |
3 ms |
12124 KB |
Output is correct |
11 |
Correct |
4 ms |
12120 KB |
Output is correct |
12 |
Correct |
3 ms |
12120 KB |
Output is correct |
13 |
Correct |
4 ms |
12120 KB |
Output is correct |
14 |
Correct |
3 ms |
12120 KB |
Output is correct |
15 |
Correct |
3 ms |
12120 KB |
Output is correct |
16 |
Correct |
4 ms |
12124 KB |
Output is correct |
17 |
Correct |
3 ms |
12120 KB |
Output is correct |
18 |
Incorrect |
5 ms |
12120 KB |
Breaking single line is causing network to disconnect. |
19 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
12124 KB |
Output is correct |
2 |
Correct |
4 ms |
12124 KB |
Output is correct |
3 |
Correct |
3 ms |
12124 KB |
Output is correct |
4 |
Correct |
4 ms |
12324 KB |
Output is correct |
5 |
Correct |
4 ms |
12280 KB |
Output is correct |
6 |
Correct |
3 ms |
12124 KB |
Output is correct |
7 |
Correct |
3 ms |
12120 KB |
Output is correct |
8 |
Correct |
3 ms |
12120 KB |
Output is correct |
9 |
Correct |
3 ms |
12120 KB |
Output is correct |
10 |
Correct |
3 ms |
12124 KB |
Output is correct |
11 |
Correct |
4 ms |
12120 KB |
Output is correct |
12 |
Correct |
3 ms |
12120 KB |
Output is correct |
13 |
Correct |
4 ms |
12120 KB |
Output is correct |
14 |
Correct |
3 ms |
12120 KB |
Output is correct |
15 |
Correct |
3 ms |
12120 KB |
Output is correct |
16 |
Correct |
4 ms |
12124 KB |
Output is correct |
17 |
Correct |
3 ms |
12120 KB |
Output is correct |
18 |
Incorrect |
5 ms |
12120 KB |
Breaking single line is causing network to disconnect. |
19 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
12124 KB |
Output is correct |
2 |
Correct |
4 ms |
12124 KB |
Output is correct |
3 |
Correct |
3 ms |
12124 KB |
Output is correct |
4 |
Correct |
4 ms |
12324 KB |
Output is correct |
5 |
Correct |
4 ms |
12280 KB |
Output is correct |
6 |
Correct |
3 ms |
12124 KB |
Output is correct |
7 |
Correct |
3 ms |
12120 KB |
Output is correct |
8 |
Correct |
3 ms |
12120 KB |
Output is correct |
9 |
Correct |
3 ms |
12120 KB |
Output is correct |
10 |
Correct |
3 ms |
12124 KB |
Output is correct |
11 |
Correct |
4 ms |
12120 KB |
Output is correct |
12 |
Correct |
3 ms |
12120 KB |
Output is correct |
13 |
Correct |
4 ms |
12120 KB |
Output is correct |
14 |
Correct |
3 ms |
12120 KB |
Output is correct |
15 |
Correct |
3 ms |
12120 KB |
Output is correct |
16 |
Correct |
4 ms |
12124 KB |
Output is correct |
17 |
Correct |
3 ms |
12120 KB |
Output is correct |
18 |
Incorrect |
5 ms |
12120 KB |
Breaking single line is causing network to disconnect. |
19 |
Halted |
0 ms |
0 KB |
- |