Submission #106442

#	Time	Username	Problem	Language	Result	Execution time	Memory
106442		RedNextCentury	Ball Machine (BOI13_ballmachine)	C++14	100 / 100	608 ms	46044 KiB

ballmachine

#include<bits/stdc++.h>
using namespace std;
vector<int> adj[1000000];
int mn[1000000];
bool cmp(int a,int b)
{
    return mn[a]<mn[b];
}
void pre(int v)
{
    mn[v]=v;
    for (auto u:adj[v])
    {
        pre(u);
        mn[v]=min(mn[v],mn[u]);
    }
}
int pa[1000001][21];
int ord[1000001];
int tt=1;
void dfs(int v)
{
    for (auto u:adj[v])
        dfs(u);
    ord[v]=tt++;
}
bool has[1000000];
int main()
{
    //freopen("out","w",stdout);
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    int n,q;
    cin>>n>>q;
    int root=-1;
    for (int i=1;i<=n;i++)
    {
        cin>>pa[i][0];
        if (pa[i][0]==0) root = i;
        else adj[pa[i][0]].push_back(i);
    }
    for (int j=1;j<=18;j++)
        for (int i=1;i<=n;i++)
            pa[i][j]=pa[pa[i][j-1]][j-1];
    pre(root);
    for (int i=1;i<=n;i++)
        sort(adj[i].begin(),adj[i].end(),cmp);
    dfs(root);
    set<pair<int,int> > s;
    for (int i=1;i<=n;i++)
        s.insert({ord[i],i});
    while(q--)
    {
        int t,v;
        cin>>t>>v;
        if (t==1)
        {
            pair<int,int> p;
            while(v--)
            {
                p = *s.begin();
                s.erase(s.begin());
                has[p.second]=1;
            }
            cout<<p.second<<endl;
        }
        else
        {
            int u = v;
            int ret=0;
            for (int i=18;i>=0;i--)
                if (has[pa[u][i]])
                    u = pa[u][i] , ret+=(1<<i);
            has[u]=0;
            s.insert({ord[u],u});
            cout<<ret<<endl;
        }
    }
}

• Subtask 1: 25 / 25
• Subtask 2: 30 / 30
• Subtask 3: 40 / 40
• Subtask 4: 5 / 5