Luogu P3203 [HNOI2010]弹飞绵羊

题目链接：​​传送门​​

指针版
建点建到
到了代表弹飞了
输入弹力系数的时候就直接
维护每个节点的子树
操作打通j到之间的重链，输出的，也就是深度
操作掉原来的边再建新边，注意判断是不是连到即可
由于它告诉你编号从~，所以把编号全体上挪一位

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <complex>
#include <algorithm>
#include <climits>
#include <queue>
#include <map>
#include <set>
#include <vector>
#include <iomanip>
#define
#define

using namespace std;
typedef long long ll;
int tot, n, m, x, y, w[A];
namespace LCT {
    struct node* null;
    struct node {
        node *ch[2], *fa;
        int siz, rev;
        bool whether() {
            return fa->ch[1] == this;
        }
        bool isroot() {
            return fa == null or (fa->ch[0] != this and fa->ch[1] != this);
        }
        void update() {
            siz = 1;
            if (ch[0] != null) siz += ch[0]->siz;
            if (ch[1] != null) siz += ch[1]->siz;
        }
        void down() {
            if (this == null or !rev) return;
            swap(ch[0], ch[1]);
            ch[0]->rev ^= 1;
            ch[1]->rev ^= 1;
            rev = 0;
        }
        void setnode(bool k, node *c) {
            down();
            ch[k] = c;
            if (c != null) c->fa = this;
        }
    }pool[A];
    #define
    void init() {
        null = pool;
        null->ch[0] = null->ch[1] = null->fa = null;
        null->siz = null->rev = 0;
    }
    ND newnode(int val) {
        ND x = pool + ++tot;
        x->ch[0] = x->ch[1] = x->fa = null;
        x->siz = 1;
        return x;
    }
    void rotate(ND x) {
        node *fa = x->fa, *grand = fa->fa;
        if (!fa->isroot()) grand->down();
        fa->down(); x->down();
        int dir = x->whether();
        fa->setnode(dir, x->ch[dir ^ 1]);
        if (fa->isroot()) x->fa = fa->fa;
        else grand->setnode(fa->whether(), x);
        x->setnode(dir ^ 1, fa);
        fa->update(); x->update();
    }
    void fix(ND x) {
        if (!x->isroot()) fix(x->fa);
        x->down();
    }
    void splay(ND x) {
        fix(x);
        while (!x->isroot()) {
            if (!x->fa->isroot())
                x->whether() == x->fa->whether() ? rotate(x->fa) : rotate(x);
            rotate(x);
        }
        x->update();
    }
    ND access(ND x) {
        ND y = null;
        while (x != null) {
            splay(x);
            x->ch[1] = y;
            x->update();
            y = x;
            x = x->fa;
        }
        return y;
    }
    void makeroot(ND x) {
        access(x)->rev = 1;
        splay(x);
    }
    void link(ND x, ND y) {
        makeroot(x);
        x->fa = y;
    }
    void cut(ND x, ND y) {
        makeroot(x);
        access(y);
        splay(x);
        if (x->ch[1] == y and x->ch[1]->ch[0] != null) return;
        x->ch[1] = y->fa = null;
    }
    int ask(int x, int y) {
        ND a = pool + x;
        ND b = pool + y;
        makeroot(a);
        access(b);
        splay(b);
        return b->siz;
    }
}

int main(int argc, char const *argv[]) {
    LCT::init();
    scanf("%d", &n);
    for (int i = 1; i <= n + 1; i++) LCT::newnode(1);
    for (int i = 1; i <= n; i++) {
        scanf("%d", &w[i]);
        LCT::ND a = LCT::pool + i;
        LCT::ND b = LCT::pool + i + w[i];
        LCT::ND c = LCT::pool + n + 1;
        if (i + w[i] <= n) LCT::link(a, b);
        else LCT::link(a, c);
    }
    scanf("%d", &m);
    while (m--) {
        int opt;
        scanf("%d", &opt);
        if (opt == 1) {
            scanf("%d", &x); x++;
            printf("%d\n", LCT::ask(x, n + 1) - 1);
        }
        else {
            scanf("%d%d", &x, &y); x++;
            LCT::ND a = LCT::pool + x;
            LCT::ND b = LCT::pool + x + w[x];
            LCT::ND c = LCT::pool + n + 1;
            LCT::ND d = LCT::pool + x + y;
            LCT::cut(a, x + w[x] <= n ? b : c);
            LCT::link(a, x + y <= n ? d : c);
            w[x] = y;
        }
    }
}