| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 79593 |
2018-10-15T04:20:46 Z |
EntityIT |
Network (BOI15_net) |
C++14 |
|
925 ms |
68644 KB |
#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define fi first
#define se second
typedef pair<int, int> ii;
const int N = 5e5 + 5;
int n, child[N], nLeaf, cur, tmp, pter[N];
vector<int> gr[N], vec[N];
void prep (int u, int p) {
for (int v : gr[u]) if (v != p) {
prep(v, u);
child[u] += child[v];
}
child[u] += (gr[u].size() == 1);
}
int findCentroid (int u, int p) {
for (int v : gr[u]) if (v != p) {
if (child[v] >= (nLeaf + 1) / 2 ) return findCentroid(v, u);
}
return u;
}
void dfs (int u, int p) {
for (int v : gr[u]) if (v != p) dfs(v, u);
if (gr[u].size() == 1) vec[cur].pb(u);
}
int main () {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n;
for (int _ = 1; _ < n; ++_) {
int u, v; cin >> u >> v;
gr[u].pb(v); gr[v].pb(u);
}
for (int u = 1; u <= n; ++u) nLeaf += (gr[u].size() == 1);
cout << (nLeaf + 1) / 2 << '\n';
prep(1, 1);
int cen = findCentroid(1, 1);
for (int u : gr[cen]) cur ++, dfs(u, cen);
priority_queue<ii> pq;
for (int i = 1; i <= cur; ++i) {
pq.push(ii(vec[i].size() - pter[i], i) );
}
while (pq.size() > 1) {
ii tmp1 = pq.top(); pq.pop();
ii tmp2 = pq.top(); pq.pop();
cout << vec[tmp1.se][ pter[tmp1.se] ] << ' ' << vec[tmp2.se][ pter[tmp2.se] ] << '\n';
pter[tmp1.se] ++; pter[tmp2.se] ++;
if (pter[tmp1.se] < vec[tmp1.se].size() ) pq.push(ii(vec[tmp1.se].size() - pter[tmp1.se], tmp1.se) );
if (pter[tmp2.se] < vec[tmp2.se].size() ) pq.push(ii(vec[tmp2.se].size() - pter[tmp2.se], tmp2.se) );
}
if (pq.size() ) {
int u = vec[pq.top().se][ pter[pq.top().se] ];
for (int v = 1; v <= n; ++v) if (gr[v].size() == 1 && v != u) { cout << v << ' ' << u << '\n'; break; }
}
return 0;
}
Compilation message
net.cpp: In function 'int main()':
net.cpp:60:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if (pter[tmp1.se] < vec[tmp1.se].size() ) pq.push(ii(vec[tmp1.se].size() - pter[tmp1.se], tmp1.se) );
~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
net.cpp:61:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if (pter[tmp2.se] < vec[tmp2.se].size() ) pq.push(ii(vec[tmp2.se].size() - pter[tmp2.se], tmp2.se) );
~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
23 ms |
23800 KB |
Output is correct |
| 2 |
Correct |
27 ms |
23944 KB |
Output is correct |
| 3 |
Correct |
23 ms |
23968 KB |
Output is correct |
| 4 |
Correct |
23 ms |
24012 KB |
Output is correct |
| 5 |
Correct |
25 ms |
24024 KB |
Output is correct |
| 6 |
Correct |
23 ms |
24024 KB |
Output is correct |
| 7 |
Correct |
23 ms |
24024 KB |
Output is correct |
| 8 |
Correct |
22 ms |
24024 KB |
Output is correct |
| 9 |
Correct |
23 ms |
24024 KB |
Output is correct |
| 10 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 11 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 12 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 13 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 14 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 15 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 16 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 17 |
Correct |
24 ms |
24140 KB |
Output is correct |
| 18 |
Correct |
25 ms |
24140 KB |
Output is correct |
| 19 |
Correct |
30 ms |
24140 KB |
Output is correct |
| 20 |
Correct |
23 ms |
24172 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
23 ms |
23800 KB |
Output is correct |
| 2 |
Correct |
27 ms |
23944 KB |
Output is correct |
| 3 |
Correct |
23 ms |
23968 KB |
Output is correct |
| 4 |
Correct |
23 ms |
24012 KB |
Output is correct |
| 5 |
Correct |
25 ms |
24024 KB |
Output is correct |
| 6 |
Correct |
23 ms |
24024 KB |
Output is correct |
| 7 |
Correct |
23 ms |
24024 KB |
Output is correct |
| 8 |
Correct |
22 ms |
24024 KB |
Output is correct |
| 9 |
Correct |
23 ms |
24024 KB |
Output is correct |
| 10 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 11 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 12 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 13 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 14 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 15 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 16 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 17 |
Correct |
24 ms |
24140 KB |
Output is correct |
| 18 |
Correct |
25 ms |
24140 KB |
Output is correct |
| 19 |
Correct |
30 ms |
24140 KB |
Output is correct |
| 20 |
Correct |
23 ms |
24172 KB |
Output is correct |
| 21 |
Correct |
23 ms |
24172 KB |
Output is correct |
| 22 |
Correct |
23 ms |
24172 KB |
Output is correct |
| 23 |
Correct |
25 ms |
24172 KB |
Output is correct |
| 24 |
Correct |
24 ms |
24316 KB |
Output is correct |
| 25 |
Correct |
27 ms |
24316 KB |
Output is correct |
| 26 |
Correct |
24 ms |
24316 KB |
Output is correct |
| 27 |
Correct |
25 ms |
24348 KB |
Output is correct |
| 28 |
Correct |
25 ms |
24348 KB |
Output is correct |
| 29 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 30 |
Correct |
25 ms |
24348 KB |
Output is correct |
| 31 |
Correct |
31 ms |
24348 KB |
Output is correct |
| 32 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 33 |
Correct |
22 ms |
24348 KB |
Output is correct |
| 34 |
Correct |
25 ms |
24348 KB |
Output is correct |
| 35 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 36 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 37 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 38 |
Correct |
26 ms |
24348 KB |
Output is correct |
| 39 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 40 |
Correct |
25 ms |
24348 KB |
Output is correct |
| 41 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 42 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 43 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 44 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 45 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 46 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 47 |
Correct |
26 ms |
24348 KB |
Output is correct |
| 48 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 49 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 50 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 51 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 52 |
Correct |
22 ms |
24348 KB |
Output is correct |
| 53 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 54 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 55 |
Correct |
22 ms |
24348 KB |
Output is correct |
| 56 |
Correct |
21 ms |
24348 KB |
Output is correct |
| 57 |
Correct |
22 ms |
24348 KB |
Output is correct |
| 58 |
Correct |
23 ms |
24348 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
23 ms |
23800 KB |
Output is correct |
| 2 |
Correct |
27 ms |
23944 KB |
Output is correct |
| 3 |
Correct |
23 ms |
23968 KB |
Output is correct |
| 4 |
Correct |
23 ms |
24012 KB |
Output is correct |
| 5 |
Correct |
25 ms |
24024 KB |
Output is correct |
| 6 |
Correct |
23 ms |
24024 KB |
Output is correct |
| 7 |
Correct |
23 ms |
24024 KB |
Output is correct |
| 8 |
Correct |
22 ms |
24024 KB |
Output is correct |
| 9 |
Correct |
23 ms |
24024 KB |
Output is correct |
| 10 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 11 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 12 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 13 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 14 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 15 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 16 |
Correct |
23 ms |
24140 KB |
Output is correct |
| 17 |
Correct |
24 ms |
24140 KB |
Output is correct |
| 18 |
Correct |
25 ms |
24140 KB |
Output is correct |
| 19 |
Correct |
30 ms |
24140 KB |
Output is correct |
| 20 |
Correct |
23 ms |
24172 KB |
Output is correct |
| 21 |
Correct |
23 ms |
24172 KB |
Output is correct |
| 22 |
Correct |
23 ms |
24172 KB |
Output is correct |
| 23 |
Correct |
25 ms |
24172 KB |
Output is correct |
| 24 |
Correct |
24 ms |
24316 KB |
Output is correct |
| 25 |
Correct |
27 ms |
24316 KB |
Output is correct |
| 26 |
Correct |
24 ms |
24316 KB |
Output is correct |
| 27 |
Correct |
25 ms |
24348 KB |
Output is correct |
| 28 |
Correct |
25 ms |
24348 KB |
Output is correct |
| 29 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 30 |
Correct |
25 ms |
24348 KB |
Output is correct |
| 31 |
Correct |
31 ms |
24348 KB |
Output is correct |
| 32 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 33 |
Correct |
22 ms |
24348 KB |
Output is correct |
| 34 |
Correct |
25 ms |
24348 KB |
Output is correct |
| 35 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 36 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 37 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 38 |
Correct |
26 ms |
24348 KB |
Output is correct |
| 39 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 40 |
Correct |
25 ms |
24348 KB |
Output is correct |
| 41 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 42 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 43 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 44 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 45 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 46 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 47 |
Correct |
26 ms |
24348 KB |
Output is correct |
| 48 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 49 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 50 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 51 |
Correct |
24 ms |
24348 KB |
Output is correct |
| 52 |
Correct |
22 ms |
24348 KB |
Output is correct |
| 53 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 54 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 55 |
Correct |
22 ms |
24348 KB |
Output is correct |
| 56 |
Correct |
21 ms |
24348 KB |
Output is correct |
| 57 |
Correct |
22 ms |
24348 KB |
Output is correct |
| 58 |
Correct |
23 ms |
24348 KB |
Output is correct |
| 59 |
Correct |
590 ms |
49188 KB |
Output is correct |
| 60 |
Correct |
603 ms |
49188 KB |
Output is correct |
| 61 |
Correct |
23 ms |
49188 KB |
Output is correct |
| 62 |
Correct |
23 ms |
49188 KB |
Output is correct |
| 63 |
Correct |
593 ms |
49188 KB |
Output is correct |
| 64 |
Correct |
27 ms |
49188 KB |
Output is correct |
| 65 |
Correct |
43 ms |
49188 KB |
Output is correct |
| 66 |
Correct |
279 ms |
49188 KB |
Output is correct |
| 67 |
Correct |
925 ms |
65296 KB |
Output is correct |
| 68 |
Correct |
871 ms |
65296 KB |
Output is correct |
| 69 |
Correct |
35 ms |
65296 KB |
Output is correct |
| 70 |
Correct |
168 ms |
65296 KB |
Output is correct |
| 71 |
Correct |
673 ms |
68644 KB |
Output is correct |
| 72 |
Correct |
607 ms |
68644 KB |
Output is correct |
| 73 |
Correct |
152 ms |
68644 KB |
Output is correct |
| 74 |
Correct |
678 ms |
68644 KB |
Output is correct |
| 75 |
Correct |
67 ms |
68644 KB |
Output is correct |
| 76 |
Correct |
551 ms |
68644 KB |
Output is correct |
| 77 |
Correct |
562 ms |
68644 KB |
Output is correct |
| 78 |
Correct |
57 ms |
68644 KB |
Output is correct |
| 79 |
Correct |
870 ms |
68644 KB |
Output is correct |
| 80 |
Correct |
25 ms |
68644 KB |
Output is correct |
| 81 |
Correct |
207 ms |
68644 KB |
Output is correct |
| 82 |
Correct |
653 ms |
68644 KB |
Output is correct |
| 83 |
Correct |
655 ms |
68644 KB |
Output is correct |
| 84 |
Correct |
680 ms |
68644 KB |
Output is correct |
| 85 |
Correct |
695 ms |
68644 KB |
Output is correct |
| 86 |
Correct |
645 ms |
68644 KB |
Output is correct |
| 87 |
Correct |
655 ms |
68644 KB |
Output is correct |
