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LCT直接上

记录子树的大小

#include<cstdio>
#include<algorithm>
using namespace std;

int n,m,Next[200005];

struct Node{
int siz,rev;
Node *ch[2],*fa;
Node(Node *fat);
void Pushup();
void Pushdown();
}*root[200005],*Null;

Node::Node(Node *fat){
ch[0]=ch[1]=Null;
fa=fat;
siz=1;
rev=0;
}

void Node::Pushup(){
siz=1;
if(ch[0]!=Null)siz+=ch[0]->siz;
if(ch[1]!=Null)siz+=ch[1]->siz;
}

void Node::Pushdown(){
if(rev){
	if(ch[0]!=Null)ch[0]->rev^=1;
	if(ch[1]!=Null)ch[1]->rev^=1;
	swap(ch[0],ch[1]);
	rev=0;
}
}

int Notroot(Node *x){
return (x->fa->ch[0]==x)||(x->fa->ch[1]==x);
}

void Prepare(Node *x){
if(Notroot(x))Prepare(x->fa);
x->Pushdown();
}

void Rotate(Node *x,int kind){
Node *y=x->fa,*z=y->fa;
y->ch[!kind]=x->ch[kind];
if(x->ch[kind]!=Null)x->ch[kind]->fa=y;
x->fa=z;
if(Notroot(y))z->ch[z->ch[1]==y]=x;
y->fa=x;
x->ch[kind]=y;
y->Pushup();
x->Pushup();
}

void Splay(Node *x){
Prepare(x);
while(Notroot(x)){
	Node *y=x->fa,*z=y->fa;
	if(!Notroot(y)){Rotate(x,y->ch[0]==x);}
	else {
		if(y->ch[1]==x && z->ch[1]==y){Rotate(y,0);Rotate(x,0);}
		else if(y->ch[1]==x && z->ch[0]==y){Rotate(x,0);Rotate(x,1);}
		else if(y->ch[0]==x && z->ch[0]==y){Rotate(y,1);Rotate(x,1);}
		else {Rotate(x,1);Rotate(x,0);}
	}
}
}

void Access(Node *x){
for(Node *y=Null;x!=Null;y=x,x=x->fa){Splay(x);x->ch[1]=y;x->Pushup();}
}

void Makeroot(Node *x){
Access(x);
Splay(x);
x->rev^=1;
}

void Link(Node *x,Node *y){
Makeroot(x);
x->fa=y;
}

void Cut(Node *x,Node *y){
Makeroot(x);
Access(y);
Splay(y);
if(y->ch[0]==x){y->ch[0]=Null;x->fa=Null;}
}

Node *Find(Node *x){
Access(x);
Splay(x);
while(x->ch[0]!=Null)x=x->ch[0];
return x;
}

Node *ToLct(int x){
return root[x];
}

Node *GetNull(){
Node *u=new Node(Null);
u->fa=u->ch[0]=u->ch[1]=u;
u->siz=0;
u->rev=0;
return u;
}

int Jump(int x){
Node *u=ToLct(x);
Makeroot(ToLct(n+1));
Access(u);
Splay(u);
return u->ch[0]->siz;
}

void Change(int x,int y){
//Node *u=ToLct(x),*v=ToLct(Next[x]);
//printf("Tp%d\n",Next[x]);
int t=min(x+y,n+1);
//printf("Tpt%d\n",t);
Cut(ToLct(x),ToLct(Next[x]));
Link(ToLct(x),ToLct(t));
Next[x]=t;
}

int main(){
freopen("2002.in","r",stdin);
freopen("2002.out","w",stdout);
Null=GetNull();
scanf("%d",&n);
root[n+1]=new Node(Null);
for(int i=1;i<=n;i++){
	int tp;
	scanf("%d",&tp);
	root[i]=new Node(Null);
	Next[i]=min(n+1,tp+i);
}
for(int i=1;i<=n;i++){
	Link(ToLct(i),ToLct(Next[i]));
}
scanf("%d",&m);
for(int i=1;i<=m;i++){
	int opt,x,y;
	scanf("%d",&opt);
	if(opt==1){scanf("%d",&x);printf("%d\n",Jump(x+1));}
	if(opt==2){scanf("%d %d",&x,&y);Change(x+1,y);}
}
return 0;
}