#include <iostream>
#include <vector>
#include <algorithm>
#include <set>
using namespace std;
using ll = long long;
#define int ll
#define fore(i, a, b) for(int i=a; i<b; ++i)
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define pb(x) push_back(x)
#define vi vector<int>
const int N = 2005;
vi adj[N];
int n;
/*int taken[N];
int dfs(int x, int prev=-1){
int tam = 1;
for(int child : adj[x]){
if(child == prev) continue;
tam += dfs(child, x);
}
if(taken[x]){
taken[x] = tam;
tam = 0;
}
return tam;
}*/
int tam[N];
void dfs(int x, int prev=-1){
tam[x] = 1;
for(int child : adj[x]){
if(child == prev) continue;
dfs(child, x);
tam[x] += tam[child];
}
}
set<pair<int,int>> parientes;
void calcParientes(int start, int x, int prev=-1){
if(start != x){
parientes.insert(make_pair(min(start, x), max(start, x)));
}
for(int child : adj[x]){
if(child == prev) continue;
calcParientes(start, child, x);
}
}
signed main(){
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin >> n;
/*
if(n <= 200){
fore(i, 0, n-1){
int u, v;
cin >> u >> v;
adj[u].pb(v);
adj[v].pb(u);
}
int ans = 1e9;
taken[1] = 1;
for(int i=2; i<=n; ++i){
for(int j=i+1; j<=n; ++j){
taken[1] = taken[i] = taken[j] = 1;
dfs(1);
ans = min(ans, max({taken[1],taken[i],taken[j]}) - min({taken[1],taken[i],taken[j]}));
taken[1] = taken[i] = taken[j] = 0;
}
}
cout << ans;
return 0;
}
*/
if(n <= 2000){
fore(i, 0, n-1){
int u, v;
cin >> u >> v;
adj[u].pb(v);
adj[v].pb(u);
}
int ans = 1e9;
dfs(1);
fore(i, 1, n+1){
calcParientes(i, i);
}
fore(i, 2, n+1){
fore(j, i+1, n+1){
int p = i;
int q = j;
if(tam[p] > tam[q]) swap(p, q);
int tam1 = tam[p];
int tam2 = tam[q];
if(parientes.count({min(p, q), max(p, q)})){
tam2 -= tam1;
}
int tam3 = n - tam1 - tam2;
ans = min(ans, max({tam1, tam2, tam3}) - min({tam1, tam2, tam3}));
}
}
cout << ans;
return 0;
}
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
7 ms |
1628 KB |
Output is correct |
2 |
Correct |
7 ms |
1624 KB |
Output is correct |
3 |
Incorrect |
7 ms |
1628 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
7 ms |
1628 KB |
Output is correct |
2 |
Correct |
7 ms |
1624 KB |
Output is correct |
3 |
Incorrect |
7 ms |
1628 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
7 ms |
1628 KB |
Output is correct |
2 |
Correct |
7 ms |
1624 KB |
Output is correct |
3 |
Incorrect |
7 ms |
1628 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |