BZOJ 2002 弹飞绵羊

Posted on 2016-04-15 19:57  ziliuziliu  阅读(84)  评论(0编辑  收藏

LCT模板题。

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#define maxn 200500
using namespace std;
int n,type,x,y,fath[maxn],size[maxn],tree[maxn][3];
int m,rev[maxn];
int next[maxn],stack[maxn],top=0;
bool isroot(int x)
{
    return tree[fath[x]][1]!=x&&tree[fath[x]][2]!=x;
}
void pushdown(int x)
{
    if (rev[x])
    {
        rev[x]=0;
        int ls=tree[x][1],rs=tree[x][2];
        rev[ls]^=1;rev[rs]^=1;
        swap(tree[x][1],tree[x][2]);
    }
}
void pushup(int now)
{
    int ls=tree[now][1],rs=tree[now][2];
    size[now]=size[ls]+size[rs]+1;
}
void rotate(int x)
{
    int y=fath[x],z=fath[y],l,r;
    if (tree[y][1]==x) l=1;else l=2;
    r=3-l;
    if (!isroot(y)) 
    {
        if (tree[z][1]==y) tree[z][1]=x;
        else tree[z][2]=x;
    }
    fath[x]=z;fath[y]=x;fath[tree[x][r]]=y;
    tree[y][l]=tree[x][r];tree[x][r]=y;
    pushup(y);pushup(x);
}
void splay(int x)
{
    top=0;
    stack[++top]=x;
    for (int i=x;!isroot(i);i=fath[i])
        stack[++top]=fath[i];
    for (int i=top;i>=1;i--)
        pushdown(stack[i]);
    while (!isroot(x))
    {
        int y=fath[x],z=fath[y];
        if (!isroot(y))
        {
            if ((tree[z][1]==y)^(tree[y][1]==x)) rotate(x);
            else rotate(y);
        }
        rotate(x);
    }
}
void access(int x)
{
    int regis=0;
    while (x)
    {
        splay(x);
        tree[x][2]=regis;
        regis=x;x=fath[x];
    }
}
void makeroot(int x)
{
    access(x);splay(x);
    rev[x]^=1;
}
void cut(int x,int y)
{
    makeroot(x);access(y);
    splay(y);tree[y][1]=0;fath[x]=0;
}
void link(int x,int y)
{
    makeroot(x);
    fath[x]=y;
    splay(x);
}
int main()
{
    scanf("%d",&n);
    for (int i=1;i<=n;i++)
    {
        scanf("%d",&type);
        fath[i]=min(n+1,i+type);
        next[i]=fath[i];
        size[i]=1;
    }    
    size[n+1]=1;
    scanf("%d",&m);
    for (int i=1;i<=m;i++)
    {
        scanf("%d",&type);
        if (type==1)
        {
            scanf("%d",&x);x++;
            makeroot(n+1);
            access(x);splay(x);printf("%d\n",size[tree[x][1]]);
        }
        else
        {
            scanf("%d%d",&x,&y);x++;
            cut(next[x],x);link(min(x+y,n+1),x);next[x]=min(x+y,n+1);
        }
    }
    return 0;
}