Submission #813721

#	Time	Username	Problem	Language	Result	Execution time	Memory
813721		dijbkr	Bosses (BOI16_bosses)	C++14	0 / 100	16 ms	24788 KiB

bosses

#include<bits/stdc++.h>
typedef long long ll;
typedef unsigned long long ull;
using namespace std;

const ll maxn=500005;

ll n;
vector<ll>adj[maxn];
vector<ll>adj_1[maxn];
ll dp[maxn];
bool used[maxn];
bool used_1[maxn];

ll DFS(ll u)
{
    used[u]=true;
    for (auto it:adj_1[u])
    {
        if (used[it]==false)
        {
            DFS(it);
            dp[u]+=dp[it];
        }
    }
    return dp[u];
}

ll BFS(ll u)
{
    memset(used,false,sizeof(used));
    memset(used_1,false,sizeof(used_1));
    queue<ll>q;
    q.push(u);
    used_1[u]=true;
    for (ll i=1; i<=n; i++) {
      adj_1[i].clear();
    }
    while (!q.empty())
    {
        ll v=q.front();
        q.pop();
        for (auto it:adj[v])
        {
            if (used_1[it]==false)
            {
                used_1[it]=true;
                adj_1[v].push_back(it);
                q.push(it);
            }
        }
    }
    ll res=0;
    DFS(u);
    for (ll i=1; i<=n; i++) {
      res+=dp[i];
    }
    return res;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    cin >> n;
    for (ll i=1; i<=n; i++)
    {
        ll t;
        cin >> t;
        while (t--)
        {
            ll x;
            cin >> x;
            adj[x].push_back(i);
        }
    }
   for (ll i=1; i<=n; i++) {
      dp[i]=1;
   }
//   adj_1[1].push_back(2);
//   adj_1[1].push_back(3);
//   adj_1[3].push_back(4);
//   cout << DFS(1);
//   cout << endl << dp[4];
//   cout << BFS(1) << endl;
//    cout << dp[1]+dp[2]+dp[3]+dp[4] << endl;
    ll ans=1e18;
    for (ll j=1; j<=n; j++)
    {
        for (ll i=1; i<=n; i++)
        {
            dp[i]=1;
        }
        //cout << j << " " << BFS(j) << endl;
        ans=min(ans,BFS(j));
    }
    cout << ans;
}

• Subtask 1: 0 / 22
• Subtask 2: 0 / 45
• Subtask 3: 0 / 33