#include <bits/stdc++.h>
using namespace std;
const int N = 2e5 + 5;
const int oo = 1e9;
#define sz(a) (int)a.size()
#define eb emplace_back
using pii = pair<int, int>;
int n;
namespace arcv {
int n;
vector<int> adj[N];
int par[N];
int sz[N];
int st[N];
int en[N];
int tour[N];
int ans = oo;
int times = 0;
multiset<int> S;
void calc_sz(int u, int p) {
par[u] = p;
sz[u] = 1;
for(int v : adj[u]) {
if(v == p)
continue;
calc_sz(v, u);
sz[u] += sz[v];
}
}
int get(int a, int b, int c) {
return max({a, b, c}) - min({a, b, c});
}
void DFS(int u, int p) {
auto it = S.lower_bound((n - sz[u]) / 2);
if(it != S.end())
ans = min(ans, get(sz[u], *it, n - sz[u] - (*it)));
if(it != S.begin())
--it;
if(it != S.end())
ans = min(ans, get(sz[u], *it, n - sz[u] - (*it)));
st[u] = ++times;
tour[times] = u;
for(int v : adj[u]) {
if(v == p)
continue;
DFS(v, u);
}
S.emplace(sz[u]);
en[u] = times;
}
void solution() {
cin >> n;
for(int i = 1; i < n; i++) {
int u, v;
cin >> u >> v;
adj[u].eb(v);
adj[v].eb(u);
}
calc_sz(1, 0);
DFS(1, 0);
for(int i = 1; i <= n; i++) {
int x = i;
while(x) {
ans = min(ans, get(sz[i], sz[x] - sz[i], n - sz[x]));
x = par[x];
}
}
cout << ans;
}
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
arcv::solution();
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
8796 KB |
Output is correct |
2 |
Correct |
2 ms |
8796 KB |
Output is correct |
3 |
Correct |
2 ms |
8796 KB |
Output is correct |
4 |
Correct |
2 ms |
8884 KB |
Output is correct |
5 |
Correct |
3 ms |
8796 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
8796 KB |
Output is correct |
2 |
Correct |
2 ms |
8796 KB |
Output is correct |
3 |
Correct |
2 ms |
8796 KB |
Output is correct |
4 |
Correct |
2 ms |
8884 KB |
Output is correct |
5 |
Correct |
3 ms |
8796 KB |
Output is correct |
6 |
Correct |
3 ms |
9052 KB |
Output is correct |
7 |
Correct |
3 ms |
9052 KB |
Output is correct |
8 |
Correct |
3 ms |
8908 KB |
Output is correct |
9 |
Correct |
3 ms |
9048 KB |
Output is correct |
10 |
Correct |
2 ms |
9052 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
8796 KB |
Output is correct |
2 |
Correct |
2 ms |
8796 KB |
Output is correct |
3 |
Correct |
2 ms |
8796 KB |
Output is correct |
4 |
Correct |
2 ms |
8884 KB |
Output is correct |
5 |
Correct |
3 ms |
8796 KB |
Output is correct |
6 |
Correct |
3 ms |
9052 KB |
Output is correct |
7 |
Correct |
3 ms |
9052 KB |
Output is correct |
8 |
Correct |
3 ms |
8908 KB |
Output is correct |
9 |
Correct |
3 ms |
9048 KB |
Output is correct |
10 |
Correct |
2 ms |
9052 KB |
Output is correct |
11 |
Correct |
193 ms |
27240 KB |
Output is correct |
12 |
Correct |
225 ms |
27220 KB |
Output is correct |
13 |
Correct |
132 ms |
27732 KB |
Output is correct |
14 |
Correct |
153 ms |
27412 KB |
Output is correct |
15 |
Correct |
174 ms |
27288 KB |
Output is correct |
16 |
Correct |
107 ms |
27088 KB |
Output is correct |
17 |
Correct |
139 ms |
27216 KB |
Output is correct |
18 |
Execution timed out |
1063 ms |
31488 KB |
Time limit exceeded |
19 |
Halted |
0 ms |
0 KB |
- |