#include <iostream>
#include <vector>
using namespace std;
vector<int> graph[300001];
int city_num,from,to;
int evaluate_result(int &search_start,int &need_num,int* been_there){
int available_neigbours = 0;
int sub_tree_res = 0;
been_there[search_start]++;
int neighbour_size = graph[search_start].size();
for(int i = 0; i<neighbour_size; i++){
int tmp = graph[search_start][i];
if(been_there[tmp] == 0){
available_neigbours++;
sub_tree_res += evaluate_result(tmp,need_num,been_there);
}
}
int res = available_neigbours-(need_num-sub_tree_res);
if(res < 0)return 0;
return res;
}
int search_init(int &need_num){
int been_there[city_num+1] = {0};
int start = 1;
return evaluate_result(start,need_num,been_there);
}
int main() {
cin>>city_num;
for(int i = 1; i<city_num; i++){
cin>>from>>to;
graph[from].push_back(to);
graph[to].push_back(from);
}
int need_num;
int start_point = 1;
int finish_point = city_num;
int result = 0;
while (start_point < finish_point) {
need_num = (start_point+finish_point)/2;
result = search_init(need_num);
if(result == 0){
finish_point = need_num;
}else{
start_point = ++need_num;
}
result = start_point;
}
cout<<result<<endl;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
7544 KB |
Output is correct |
2 |
Correct |
9 ms |
7548 KB |
Output is correct |
3 |
Correct |
8 ms |
7588 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
8 ms |
7588 KB |
Output is correct |
2 |
Correct |
8 ms |
7588 KB |
Output is correct |
3 |
Correct |
9 ms |
7588 KB |
Output is correct |
4 |
Correct |
9 ms |
7588 KB |
Output is correct |
5 |
Correct |
8 ms |
7588 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
8 ms |
7588 KB |
Output is correct |
2 |
Correct |
9 ms |
7588 KB |
Output is correct |
3 |
Correct |
8 ms |
7588 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
10 ms |
7748 KB |
Output is correct |
2 |
Correct |
10 ms |
7748 KB |
Output is correct |
3 |
Correct |
10 ms |
7748 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
23 ms |
7888 KB |
Output is correct |
2 |
Correct |
22 ms |
8272 KB |
Output is correct |
3 |
Correct |
18 ms |
8272 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
64 ms |
8784 KB |
Output is correct |
2 |
Correct |
56 ms |
10196 KB |
Output is correct |
3 |
Correct |
41 ms |
10196 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
208 ms |
11340 KB |
Output is correct |
2 |
Correct |
297 ms |
14176 KB |
Output is correct |
3 |
Correct |
207 ms |
14176 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
963 ms |
15040 KB |
Output is correct |
2 |
Correct |
1055 ms |
22020 KB |
Output is correct |
3 |
Correct |
462 ms |
22020 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1731 ms |
22020 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1743 ms |
22020 KB |
Output is correct |
2 |
Correct |
1736 ms |
26928 KB |
Output is correct |
3 |
Correct |
497 ms |
26928 KB |
Output is correct |