#include <bits/stdc++.h>
//#pragma GCC optimize("Ofast")
//#pragma GCC target ("avx2")
#define ll long long
#define ff first
#define ss second
#define int ll
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define pb push_back
#define pii pair <int, int>
using namespace std;
const int inf = 1e15;
const int mod = 1e9+7;
const int N = 2e5+100;
vector < vector <int> > g(N);
vector <int> sz(N), sz2(N);
void dfs(int v, int pr = -1){
sz[v] = 1;
for (auto to : g[v]){
if (to == pr) continue;
dfs(to, v);
sz[v] += sz[to];
}
}
void dfs2(int v, int cl, int pr = -1){
sz2[v] = 1;
for (auto to : g[v]){
if (to == pr || to == cl) continue;
dfs2(to, cl, v);
sz2[v] += sz2[to];
}
}
void solve(){
int n;
cin >> n;
for (int i = 1; i < n; ++i){
int a, b;
cin >> a >> b;
g[a].pb(b);
g[b].pb(a);
}
dfs(1);
int ans = inf;
for (int i = 2; i <= n; ++i){
sz2.clear(); sz2.resize(n+1);
dfs2(1, i);
vector <int> a(3); a[0] = sz[i];
int mx = n - sz[i];
for (int j = 1; j <= n; ++j){
if (!sz2[j]) continue;
int cur = max(sz2[j], n - sz[i] - sz2[j]);
mx = min(mx, cur);
}
a[1] = mx;
a[2] = n - a[0] - a[1];
sort(all(a));
if (a[0]) ans = min(ans, a[2] - a[0]);
}
cout << ans;
}
signed main(){
ios::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
int tt = 1;
//cin >> tt;
while (tt--){
solve();
cout << '\n';
}
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
8156 KB |
Output is correct |
2 |
Correct |
5 ms |
8084 KB |
Output is correct |
3 |
Correct |
5 ms |
8140 KB |
Output is correct |
4 |
Correct |
5 ms |
8140 KB |
Output is correct |
5 |
Correct |
6 ms |
8060 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
8156 KB |
Output is correct |
2 |
Correct |
5 ms |
8084 KB |
Output is correct |
3 |
Correct |
5 ms |
8140 KB |
Output is correct |
4 |
Correct |
5 ms |
8140 KB |
Output is correct |
5 |
Correct |
6 ms |
8060 KB |
Output is correct |
6 |
Correct |
67 ms |
8176 KB |
Output is correct |
7 |
Correct |
70 ms |
8232 KB |
Output is correct |
8 |
Correct |
55 ms |
8164 KB |
Output is correct |
9 |
Correct |
64 ms |
8236 KB |
Output is correct |
10 |
Correct |
81 ms |
8240 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
8156 KB |
Output is correct |
2 |
Correct |
5 ms |
8084 KB |
Output is correct |
3 |
Correct |
5 ms |
8140 KB |
Output is correct |
4 |
Correct |
5 ms |
8140 KB |
Output is correct |
5 |
Correct |
6 ms |
8060 KB |
Output is correct |
6 |
Correct |
67 ms |
8176 KB |
Output is correct |
7 |
Correct |
70 ms |
8232 KB |
Output is correct |
8 |
Correct |
55 ms |
8164 KB |
Output is correct |
9 |
Correct |
64 ms |
8236 KB |
Output is correct |
10 |
Correct |
81 ms |
8240 KB |
Output is correct |
11 |
Execution timed out |
1097 ms |
18020 KB |
Time limit exceeded |
12 |
Halted |
0 ms |
0 KB |
- |