bzoj 2002（LCT）

传送门
将能跳到的点作为当前点的father，记录子树大小siz，维护动态树即可。
注意：在rotate()时一定要记得pushup()，还有rotate()里好几个ch[ ][ ]修改不要写错了。
*此题还可以用分块解决，后面有空再填坑

#include
using namespace std;
const int MAXN=2e5+2;
int n,m;
int siz[MAXN],ch[MAXN][2],fa[MAXN],nxt[MAXN];
bool rev[MAXN];
inline int read() {
    int x=0;char c=getchar();
    while (c<'0'||c>'9') c=getchar();
    while (c>='0'&&c<='9') x=x*10+c-'0',c=getchar();
    return x;
}
inline bool isroot(int rt) {
    return ch[fa[rt]][1]!=rt&&ch[fa[rt]][0]!=rt;
}
inline void pushup(int rt) {
    siz[rt]=siz[ch[rt][0]]+siz[ch[rt][1]]+1;
}
void pushdown(int rt) {
    if (!isroot(rt)) pushdown(fa[rt]);
    if (rev[rt]) {
        rev[rt]=0;
        rev[ch[rt][0]]^=1,
        rev[ch[rt][1]]^=1;
        swap(ch[rt][0],ch[rt][1]);
    }
}
inline void rotate(int rt) {
    int f=fa[rt],which=(ch[f][1]==rt),r=isroot(f);
    ch[f][which]=ch[rt][!which],ch[rt][!which]=f,fa[ch[f][which]]=f;
    fa[rt]=fa[f],fa[f]=rt;
    if (!r)
        ch[fa[rt]][ch[fa[rt]][1]==f]=rt;
    pushup(f),pushup(rt);
}
inline void splay(int rt) {
    pushdown(rt);
    while (!isroot(rt)) {
        int f=fa[rt],ff=fa[f];
        if (isroot(f))
            rotate(rt);
        else if ((ch[ff][1]==f)==(ch[f][1]==rt))
            rotate(f),rotate(rt);
        else
            rotate(rt),rotate(rt);
    }
}
inline int access(int rt) {
    int s=0;
    while (rt) {
        splay(rt),
        ch[rt][1]=s,
        s=rt,rt=fa[rt];
    }
    return s;
}
inline void makeroot(int rt) {
    access(rt),splay(rt),rev[rt]^=1;
}
inline void link(int x,int y) {
    makeroot(x),fa[x]=y;
}
inline void cut(int x,int y) {
    makeroot(x),access(y),splay(y),fa[x]=ch[y][0]=0;
}
int main() {
//  freopen("bzoj 2002.in","r",stdin);
    memset(rev,false,sizeof(rev));
    n=read();
    for (register int i=1;i<=n;++i) {
        int x=read();
        nxt[i]=fa[i]=(x+i>n)?n+1:x+i,
        siz[i]=1;
    }
    siz[n+1]=1;
    int m=read();
    for (register int i=1;i<=m;++i) {
        int flag=read();
        if (flag^1) {
            int x=read()+1,y=read();
            int t=min(x+y,n+1);
            cut(x,nxt[x]),link(x,nxt[x]=t);
        }
        else {
            makeroot(n+1);
            int x=read()+1;
            access(x),splay(x);
            printf("%d\n",siz[ch[x][0]]);
        }
    }
    return 0;
}