【HYSBZ】2002 Bounce 弹飞绵羊

#include<cstdio>
#include<cstring>
#include<iostream>
#define MAXN 200010
using namespace std;
struct LCT {
    int bef[MAXN];
    int next[MAXN][2], pre[MAXN], key[MAXN], sum[MAXN];
    void Init() {
        memset(next, 0, sizeof(next));
        memset(pre, 0, sizeof(pre));
    }
    inline void PushUp(int x) {
        sum[x] = key[x] + sum[next[x][0]] + sum[next[x][1]];
    }
    void Rotate(int x, int kind) {
        int y, z;
        y = pre[x];
        z = pre[y];
        next[y][!kind] = next[x][kind];
        pre[next[x][kind]] = y;
        next[z][next[z][1] == y] = x;
        pre[x] = z;
        next[x][kind] = y;
        pre[y] = x;
        PushUp(y);
    }
    void Splay(int x) {
        int rt;
        for (rt = x; pre[rt]; rt = pre[rt])
            ;
        if (rt != x) {
            bef[x] = bef[rt];
            bef[rt] = 0;
            while (pre[x]) {
                if (next[pre[x]][0] == x)
                    Rotate(x, 1);
                else
                    Rotate(x, 0);
            }
            PushUp(x);
        }
    }
    void Access(int x) {
        int father;
        for (father = 0; x; x = bef[x]) {
            Splay(x);
            bef[next[x][1]] = x;
            bef[father] = 0;
            pre[next[x][1]] = 0;
            next[x][1] = father;
            pre[father] = x;
            father = x;
            PushUp(x);
        }
    }
    int Query(int x) {
        Access(x);
        Splay(x);
        return sum[next[x][0]];
    }
    void Cut(int x) {
        Access(x);
        Splay(x);
        bef[next[x][0]] = bef[x];
        bef[x] = 0;
        pre[next[x][0]] = 0;
        next[x][0] = 0;
    }
    void Join(int x, int y) {
        Cut(x);
        bef[x] = y;
    }
} lct;
int K[MAXN];
int INT() {
    int res;
    char ch;
    while (ch = getchar(), !isdigit(ch))
        ;
    for (res = ch - '0'; ch = getchar(), isdigit(ch);)
        res = res * 10 + ch - '0';
    return res;
}
int main() {
    int n, i;
    int q, x, y, cmd;
    while (~scanf("%d", &n)) {
        lct.Init();
        for (i = 1; i <= n; i++) {
            K[i] = INT();
            if (i + K[i] > n)
                lct.bef[i] = 0;
            else
                lct.bef[i] = i + K[i];
            lct.key[i] = lct.sum[i] = 1;
        }
        q = INT();
        while (q--) {
            cmd = INT(), x = INT() + 1;
            if (cmd == 1)
                printf("%d\n", lct.Query(x) + 1);
            else {
                y = INT();
                K[x] = y;
                if (x + y > n)
                    y = 0;
                else
                    y = x + y;
                lct.Join(x, y);
            }
        }
    }
    return 0;
}