#include <bits/stdc++.h>
#define int long long
#define float long double
#define pii pair<int, int>
#define tii tuple<int, int, int>
#define f first
#define s second
#define ve vector
#define emb emplace_back
#define em emplace
using namespace std;
const int inf = 1e18;
const int mod = 1e9 + 7;
int32_t main() {
ios_base::sync_with_stdio(0); cin.tie(0);
int n;
cin >> n;
ve<ve<int>> inv(n);
for (int i = 0; i < n; i++) {
int k;
cin >> k;
while (k--) {
int x;
cin >> x;
inv[x-1].emb(i);
}
}
function<int(int, int, ve<ve<int>>&, ve<int>&)> dfs = [&](int x, int par, ve<ve<int>>& adj, ve<int>& val) {
int sum = 0;
for (auto e : adj[x]) if (e != par) sum += dfs(e, x, adj, val);
return val[x] = sum + 1;
};
int mn = inf;
for (int i = 0; i < n; i++) {
queue<pii> q;
ve<bool> vis(n, false);
ve<ve<int>> adj(n);
q.em(i, -1), vis[i] = true;
int cnt = 1;
while (!q.empty()) {
auto [x, y] = q.front();
q.pop();
for (auto e : inv[x]) {
if (e == y || vis[e]) continue;
adj[x].emb(e), vis[e] = true, cnt++, q.em(e, x);
}
}
if (cnt != n) continue;
ve<int> val(n);
dfs(i, -1, adj, val);
int sum = 0;
for (auto e : val) sum += e;
mn = min(mn, sum);
}
cout << mn;
}
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |