#128. 【NOI2015】软件包管理器

[code]#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;

#define MAXN 100010

int seg[MAXN*4],sum[MAXN*4];
int fa[MAXN],size[MAXN],son[MAXN],top[MAXN],depth[MAXN],loc[MAXN];
int tot,g[MAXN*2],nnext[MAXN*2],num[MAXN*2];
int team[MAXN],head,tail;
int n,q;
void Add(int x,int y)
{
    tot++;
    nnext[tot]=g[x];
    g[x]=tot;
    num[tot]=y;
}
void Pou()
{   
    depth[1]=1;
    team[++tail]=1;
    while(head<tail)
    {
        int x=team[++head];
        for(int i=g[x];i;i=nnext[i])
        {
            int tmp=num[i];
            if(tmp==fa[x]) continue;
            fa[tmp]=x;
            team[++tail]=tmp;
        }
    }
    for(int i=n;i>=1;i--)
    {
        int x=team[i];
        size[x]=1;
        for(int j=g[x];j;j=nnext[j])
        {
            int tmp=num[j];
            if(tmp==fa[x]) continue ;
            size[x]+=size[tmp]; 
            if(size[tmp]>size[son[x]]) son[x]=tmp;
        }
    }
    top[1]=1;
    loc[1]=1;
    for(int i=1;i<=n;i++)
    {
        int x=team[i];
        int cnt=loc[x];
        if(son[x]!=0)
        {
            loc[son[x]]=++cnt;
            cnt+=size[son[x]]-1;
            top[son[x]]=top[x];
        }
        for(int j=g[x];j;j=nnext[j])
        {
            int tmp=num[j];
            if(loc[tmp]!=0) continue;
            loc[tmp]=++cnt;
            cnt+=size[tmp]-1;
            top[tmp]=tmp;
        }
    }
}

int mark[MAXN*4];
void Pushdown(int now,int l,int r)
{
    if(mark[now]==0||l==r) return ;
    int k=mark[now]-1;mark[now]=0;
    mark[now*2]=mark[now*2+1]=k+1;
    int mid=(l+r)/2;
    seg[now*2]=k*(mid-l+1);
    seg[now*2+1]=k*(r-(mid+1)+1);
}
void Change(int now,int l,int r,int s,int t,int k)
{
    if(s<=l&&r<=t)
    {
        seg[now]=(r-l+1)*k;
        mark[now]=k+1;
        return ;
    }
    Pushdown(now,l,r);
    int mid=(l+r)/2;
    if(s<=mid) Change(now*2,l,mid,s,t,k);
    if(mid+1<=t) Change(now*2+1,mid+1,r,s,t,k);
    seg[now]=seg[now*2]+seg[now*2+1];   
}
int Q(int now,int l,int r,int s,int t)
{
    if(s<=l&&r<=t)
    {
        return seg[now];
    }
    Pushdown(now,l,r);
    int mid=(l+r)/2,ans=0;
    if(s<=mid) ans+=Q(now*2,l,mid,s,t);
    if(mid+1<=t) ans+=Q(now*2+1,mid+1,r,s,t);
    return ans;
}
int Solve(int x)
{
    int ans=0;
    while(top[x]!=1)
    {
        ans+=(loc[x]-loc[top[x]]+1)-Q(1,1,n,loc[top[x]],loc[x]);
        Change(1,1,n,loc[top[x]],loc[x],1);
        x=fa[top[x]];
    }
    ans+=(loc[x]-loc[1]+1)-Q(1,1,n,loc[1],loc[x]);
    Change(1,1,n,loc[1],loc[x],1);
    return ans;
}
int main()
{
    cin >>n;
    for(int i=1;i<n;i++)
    {
        int x;
        scanf("%d",&x);
        Add(i+1,x+1);
        Add(x+1,i+1);
    }
    Pou();
    cin >>q;
    while(q--)
    {
        char s[200];
        int x;
        scanf("%s %d",s+1,&x);x++;
        if(s[1]=='u')
        {

            printf("%d\n",Q(1,1,n,loc[x],loc[x]+size[x]-1));
            Change(1,1,n,loc[x],loc[x]+size[x]-1,0);
        }
        else
        {
            printf("%d\n",Solve(x));        
        }
    }
    return 0;
}