#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;
const int MAXN = 1000001;
vector<int> adj[MAXN];
bool visited[MAXN];
int Check(int u, int k) {
int numChildren = 0, sumTree = 0;
visited[u] = true;
for (int i = 0; i < (int)adj[u].size(); i++)
if (!visited[adj[u][i]]) {
numChildren++;
sumTree += Check(adj[u][i], k);
}
return max(0, numChildren+sumTree-k);
}
int main() {
int ret, N, fromSearch = 0, toSearch;
ret = scanf("%d", &N);
if (ret < 0)
return 0;
for (int i = 0; i < N-1; i++) {
int u, v;
ret = scanf("%d%d", &u, &v);
u--;
v--;
adj[u].push_back(v);
adj[v].push_back(u);
}
toSearch = N;
while (fromSearch < toSearch) {
int centSearch = (fromSearch+toSearch)/2;
fill(visited, visited+N, false);
if (Check(0, centSearch) == 0)
toSearch = centSearch;
else
fromSearch = centSearch+1;
}
printf("%d\n", fromSearch);
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
22 ms |
23800 KB |
Output is correct |
2 |
Correct |
22 ms |
23880 KB |
Output is correct |
3 |
Correct |
22 ms |
23880 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
22 ms |
23888 KB |
Output is correct |
2 |
Correct |
25 ms |
23888 KB |
Output is correct |
3 |
Correct |
26 ms |
23960 KB |
Output is correct |
4 |
Correct |
25 ms |
23976 KB |
Output is correct |
5 |
Correct |
25 ms |
23976 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
25 ms |
23980 KB |
Output is correct |
2 |
Correct |
25 ms |
23980 KB |
Output is correct |
3 |
Correct |
26 ms |
23984 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
30 ms |
23988 KB |
Output is correct |
2 |
Correct |
22 ms |
23988 KB |
Output is correct |
3 |
Correct |
21 ms |
23996 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
31 ms |
24380 KB |
Output is correct |
2 |
Correct |
31 ms |
24568 KB |
Output is correct |
3 |
Correct |
27 ms |
24604 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
58 ms |
25408 KB |
Output is correct |
2 |
Correct |
59 ms |
26340 KB |
Output is correct |
3 |
Correct |
44 ms |
26340 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
155 ms |
28372 KB |
Output is correct |
2 |
Correct |
163 ms |
30404 KB |
Output is correct |
3 |
Correct |
121 ms |
30404 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
782 ms |
33416 KB |
Output is correct |
2 |
Correct |
701 ms |
38732 KB |
Output is correct |
3 |
Correct |
221 ms |
38732 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1096 ms |
38772 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1060 ms |
38772 KB |
Output is correct |
2 |
Correct |
1057 ms |
43664 KB |
Output is correct |
3 |
Correct |
336 ms |
43664 KB |
Output is correct |