第二个点一直WA，且伴随着提交次数（随机数种子）的变化，错误的行数还不一样。求调。

#include <bits/stdc++.h>
using namespace std;
const int N = 4e5 + 100;
long long seed = time(0);
mt19937 gen(seed);
int rnd(){return gen();}
int lc[N], rc[N], val[N], siz[N], dat[N], fa[N], tg[N];
int rt;
void init(int id, int x){
    val[id] = x;siz[id] = 1;
    fa[id] = lc[id] = rc[id] = tg[id] = 0;
    dat[id] = rnd();
}
void push_up(int u){
    siz[u] = siz[lc[u]] + siz[rc[u]] + 1;
    if(lc[u]) fa[lc[u]] = u;
    if(rc[u]) fa[rc[u]] = u;
}
void push_down(int u){
    if(!tg[u]) return ;
    if(lc[u]) tg[lc[u]] = val[lc[u]] = tg[u];
    if(rc[u]) tg[rc[u]] = val[rc[u]] = tg[u];
    tg[u] = 0;
}
// void ast1(bool c){
//     if(!c){
//         cout << 1 << "\n";
//         exit(0);
//     }
// }
// void ast2(bool c){
//     if(!c){
//         cout << 2 << "\n";
//         exit(0);
//     }
// }
// void ast3(bool c){
//     if(!c){
//         cout << 3  << "\n";
//         exit(0);
//     }
// }
pair<int, int> split_val(int u, int k){
    if(!u) return make_pair(0, 0);
    push_down(u);
    if(val[u] > k){
        auto[x, y] = split_val(lc[u], k);
        lc[u] = y;push_up(u);
        return make_pair(x, u);
    }
    else{
        auto[x, y] = split_val(rc[u], k);
        rc[u] = x;push_up(u);
        return make_pair(u, y);
    }
}
pair<int, int> split_siz(int u, int k){
    if(!u) return make_pair(0, 0);
    push_down(u);
    if(siz[lc[u]] >= k){
        auto[x, y] = split_siz(lc[u], k);
        lc[u] = y;
        push_up(u);
        return make_pair(x, u);
    }
    else{
        auto[x, y] = split_siz(rc[u], k - siz[lc[u]] - 1);
        rc[u] = x;
        push_up(u);
        return make_pair(u, y);
    }
}
int merge(int x, int y){
    if(!x || !y) return x + y;
    push_down(x);push_down(y);
    if(dat[x] < dat[y]){
        //cerr << "x = " << x << " rson:merge rc[x] = " << rc[x] << " & y = " << y << "\n";
        rc[x] = merge(rc[x], y);
        //cerr << x << " " << rc[x] << "\n";
        push_up(x);
        return x;
    }
    else{
        //cerr << "y = " << y << " lson:merge x = " << x << " & lc[y] = " << lc[y] << "\n";
        lc[y] = merge(x, lc[y]);
        //cerr << y << " " << lc[y] << "\n";
        push_up(y);
        return y;
    }
}
void upd(int u){
    if(fa[u]) upd(fa[u]);
    push_down(u);
}
int get_smler(int u){ 
    upd(u);
    int sum = siz[lc[u]] + 1;
    while(fa[u]){
        if(rc[fa[u]] == u) sum += siz[lc[fa[u]]] + 1;
        u = fa[u];
    }
    return sum;
}
void cov(int u, int k){
    if(!u) return ;
    val[u] = k;tg[u] = k;
}
void de(int u){
    if(!u) return ;
    push_down(u);
    if(lc[u]) de(lc[u]); 
    cout << val[u] << " ";
    //cout << u << ":" << val[u] << " " << lc[u] << " " << rc[u] << "\n";
    if(rc[u]) de(rc[u]);
}
int main(){
    //cerr << "seed = " << seed << "\n";
    //freopen("in.txt","r",stdin);
    //freopen("out.txt","w",stdout);
    ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
    int n;cin >> n;
    for(int i = 1, v;i <= n;i++){
        cin >> v;
        auto [x, y] = split_val(rt, v - 1);
        fa[x] = fa[y] = 0;
        init(i, v);
        rt = merge(merge(x, i), y);
    }
    // printf("After operation %d\nthe Tree:\n",1);
    // de(rt);
    // cout << "\n";
    // printf("The Fathers:");
    // for(int j = 1;j <= n;j++) cout << fa[j] << " ";
    // cout << "\n";
    // printf("The sequence:");
    // for(int j = 1;j <= n;j++) cout << val[j] << " ";
    // cout << "\n";
    int q;cin >> q;
    int op, u, v, l, r;
    for(int i = 1;i <= q;i++){
        cin >> op;
        if(op == 1){
            cin >> u >> v;
            int sml = get_smler(u) - 1;
            auto [x, rit] = split_siz(rt, sml);
            fa[x] = fa[rit] = 0;
           // de(x);cout << "|||";de(rit);cout << "\n";

            auto [usl, y] = split_siz(rit, 1);
            //de(x);cout << "|||";de(y);cout << "\n";
            fa[usl] = fa[y] = 0;
            rt = merge(x, y);
            auto [sm, bg] = split_val(rt, v - 1);
            fa[sm] = fa[bg] = 0;
            init(u, v);
            //de(sm);cout << "|||";de(u);cout << "|||";de(bg);cout << "\n";
            //cerr << "Start Merging1\n" << sm << "/" << u << "/" << bg << "\n";
            rt = merge(merge(sm, u), bg);
        }
        else if(op == 2){
            cin >> u;
            cout << val[u] << "\n";
        }
        else{
            cin >> l >> r;
            int mid = (l + r) >> 1;
            auto[lft, tp] = split_val(rt, l - 1);
            fa[lft] = fa[tp] = 0;
            auto[t, rit] = split_val(tp, r);
            fa[t] = fa[rit] = 0;
            auto[x, y] = split_val(t, (l + r) / 2);
            fa[x] = fa[y] = 0;
            cov(x, l - 1);cov(y, r + 1);
            //cerr << "Start Merging2\n";
            rt = merge(merge(lft, x), merge(y, rit));
        }
        // printf("After operation %d\nthe Tree:\n",i);
        // de(rt);
        // cout << "\n";
        // printf("The Fathers:");
        // for(int j = 1;j <= n;j++) cout << fa[j] << " ";
        // cout << "\n";
        // printf("The sequence:");
        // for(int j = 1;j <= n;j++) cout << val[j] << " ";
        // cout << "\n";
    }
    return 0;
}