【bzoj4196】[Noi2015]软件包管理器

裸的树链剖分。

对于安装 查询和维护到根路径

对于卸载 查询和维护子树信息

一开始线段树add[]标记要全赋值为-1

 #include<algorithm>
 #include<iostream>
 #include<cstdlib>
 #include<cstring>
 #include<cstdio>
 #include<cmath>
 using namespace std;

 typedef long long LL;

 #define N 200010

 int id;
 int fa[N],siz[N],top[N],son[N];
 int pos[N],r[N];
 LL sum[N<<],add[N<<];

 struct Node
 {
     int to,next;
 }e[N];
 int head[N];
 int cnt;

 int a;

 char s;

 int n,q;

 int read()
 {
     int x=,f=;char ch=getchar();
     while(ch<''||ch>''){if(ch=='-')f=-;ch=getchar();}
     while(ch>=''&&ch<=''){x=x*+ch-'';ch=getchar();}
     return x*f;
 }

 void link(int x,int y)
 {
     e[++cnt]=(Node){y,head[x]};
     head[x]=cnt;
 }

 void dfs(int x)
 {
     siz[x]=;
     for (int i=head[x],mx=;i;i=e[i].next)
         if (e[i].to!=fa[x])
         {
             fa[e[i].to]=x;
             dfs(e[i].to);
             siz[x]+=siz[e[i].to];
             if (siz[e[i].to]>mx)
                 mx=siz[e[i].to],son[x]=e[i].to;
         }
 }

 void dfs2(int x,int cha)
 {
     top[x]=cha;
     pos[x]=++id;
     if (son[x])
         dfs2(son[x],cha);
     for (int i=head[x];i;i=e[i].next)
         if(e[i].to!=fa[x] && e[i].to!=son[x])
             dfs2(e[i].to,e[i].to);
     r[x]=id;
 }

 void pushup(int now)
 {
     sum[now]=sum[now<<]+sum[now<<|];
 }

 void pushdown(int nowl,int nowr,int now,int mid)
 {
     if (add[now]!=-)
     {
         LL t=add[now];
         add[now]=-;
         add[now<<]=t;
         add[now<<|]=t;
         sum[now<<]=t*(mid-nowl+);
         sum[now<<|]=t*(nowr-mid);
     }
 }

 void update(int nowl,int nowr,int now,int s,int t,LL d)
 {
     if (nowl>=s && nowr<=t)
     {
         add[now]=d;
         sum[now]=(nowr-nowl+)*d;
         return ;
     }
     int mid=(nowl+nowr)>>;
     pushdown(nowl,nowr,now,mid);
     if (s<=mid)
         update(nowl,mid,now<<,s,t,d);
     if (t>mid)
         update(mid+,nowr,now<<|,s,t,d);
     pushup(now);
 }

 int query(int nowl,int nowr,int now,int s,int t)
 {
     if (nowl>=s && nowr<=t)
         return sum[now];
     int mid=(nowl+nowr)>>;
     int ans=;
     pushdown(nowl,nowr,now,mid);
     if (s<=mid)
         ans+=query(nowl,mid,now<<,s,t);
     if (t>mid)
         ans+=query(mid+,nowr,now<<|,s,t);
     return ans;
 }

 int work1(int x)
 {
     int ans,res=;
     while (x)
     {
         ans=query(,n,,pos[top[x]],pos[x]);
         res+=pos[x]-pos[top[x]]+-ans;
         update(,n,,pos[top[x]],pos[x],);
         if (ans)
             break;
         x=fa[top[x]];
     }
     return res;
 }

 int work2(int x)
 {
     int res;
     res=query(,n,,pos[x],r[x]);
     update(,n,,pos[x],r[x],);
     return res;
 }

 int main()
 {
      n=read();
     for (int i=;i<n;i++)
     {
         a=read();
         link(a+,i+);
     }
     dfs();
     dfs2(,);
     memset(add,-,sizeof(add));
     q=read();
     while (q--)
     {
         scanf("%c",&s);
         a=read();
         if (s=='i')
             printf("%d\n",work1(a+));
         else
             printf("%d\n",work2(a+));
     }
     return ;
 }