Submission #859260

#	Time	Username	Problem	Language	Result	Execution time	Memory
859260		8pete8	Ball Machine (BOI13_ballmachine)	C++14	65.57 / 100	1075 ms	42152 KiB

ballmachine

#include<iostream>
#include<stack>
#include<map>
#include<vector>
#include<string>
#include<unordered_map>
#include <queue>
#include<cstring>
#include<limits.h>
#include<cmath>
#include<set>
#include<algorithm>
#include<bitset>
#include<list>
using namespace std;
#define ll long long
#define f first
#define endl "\n"
#define s second
#define pii pair<int,int>
#define ppii pair<int,pii>
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define F(n) for(int i=0;i<n;i++)
#define lb lower_bound
#define ub upper_bound
//#define p push
#define pb push_back
#define fastio ios::sync_with_stdio(false);cin.tie(NULL);
using namespace std;
#define int long long
const int mxn=1e5,mod=69,lg=30,root=80,inf=1e18;
vector<ppii>adj[mxn+10];
int up[mxn+10][lg+5],h[mxn+10],st,go[mxn+10];
bitset<mxn+10>on;
int ch=0;
int dfs(int cur,int p){
    int cm=inf;
    for(auto &i:adj[cur]){
        h[i.f]=h[cur]+1;
        ch=max(ch,h[i.f]);
        int k=dfs(i.f,cur);
        cm=min(cm,k);
        i.s.f=k;
    }
    return min(cm,cur);
}
int solve(int cur,int p){
    int cm=inf;
    for(auto &i:adj[cur])cm=min(cm,i.s.f);
    for(auto &i:adj[cur]){
        i.s.s=solve(i.f,cur);
        if(i.s.f==cm)go[cur]=i.s.s;
    }
    if(cm==inf)return go[cur]=cur;
    return go[cur];
}
int32_t main(){
    fastio
    int n,m;cin>>n>>m;
    for(int i=1;i<=n;i++){
        int a;cin>>a;
        if(a==0){
            st=i;
            continue;
        }
        adj[a].pb({i,{-1,-1}});
        up[i][0]=a;
    }
    priority_queue<pii>pq;
    dfs(st,-1);
    solve(st,-1);
    for(int j=1;j<=lg;j++)for(int i=1;i<=n;i++)up[i][j]=up[up[i][j-1]][j-1];
    while(m--){
        int t;cin>>t;
        if(t==1){
            int k;cin>>k; 
            int ans=0;
            for(int j=0;j<k;j++){
                while(!pq.empty()&&!on[pq.top().s])pq.pop();
                while(!pq.empty()&&on[up[pq.top().s][0]])pq.pop();
                if(pq.empty())pq.push({h[go[st]],go[st]}),on[go[st]]=true,ans=go[st];
                else{
                    int cur=pq.top().s;
                    cur=up[cur][0];
                    int cm=inf;
                    pq.pop();
                    for(auto i:adj[cur])if(!on[i.f])cm=min(cm,i.s.f);
                    for(auto i:adj[cur]){
                        if(i.s.f==cm){
                            pq.push({h[i.s.s],i.s.s}),on[i.s.s]=true,ans=i.s.s;
                            break;
                        }
                    }
                    if(cm==inf){
                        on[cur]=true;
                        ans=cur;
                        pq.push({h[cur],cur});
                    }
                }
            }
            cout<<ans<<'\n';
        }   
        else{
            int x,y,diff;cin>>x;
            y=x;
            for(int i=lg;i>=0;i--)if(on[up[x][i]])x=up[x][i];
            diff=h[y]-(h[x]+1);
            for(int i=0;i<=lg;i++)if(diff&(1<<i))y=up[y][i];
            on[x]=false;
            if(diff!=-1)pq.push({h[y],y});
            else{for(auto i:adj[x])pq.push({h[i.f],i.f});}
            cout<<diff+1<<'\n';
        }
    }
}

• Subtask 1: 9.615384615384615 / 25
• Subtask 2: 17.142857142857142 / 30
• Subtask 3: 37.142857142857146 / 40
• Subtask 4: 1.6666666666666667 / 5