求差错，TLE * 7，WA * 1

写的 Splay，已经一下午了 5555

#include <cstdio>
#include <cstring>
#include <string>
#include <iostream>
#include <algorithm>
#define MAXN 1100001

int n, m, last, ans;

namespace Splay {
    int root, fa[MAXN], size[MAXN], son[MAXN][2];
    int num, val[MAXN], cnt[MAXN];
    int which(int x) { return son[fa[x]][1] == x ? 1 : 0; }
    void update(int x) { size[x] = cnt[x] + size[son[x][0]] + size[son[x][1]]; }
    void clear(int x) { fa[x] = son[x][0] = son[x][1] = size[x] = cnt[x] = val[x] = 0; }
    void rotate(int x) {
        int father = fa[x], grandpa = fa[father];
        int flag1 = which(x), flag2 = which(father);
        fa[x] = grandpa;
        if (grandpa) son[grandpa][flag2] = x;
        fa[son[x][flag1 ^ 1]] = father;
        son[father][flag1] = son[x][flag1 ^ 1];
        son[x][flag1 ^ 1] = father;
        fa[father] = x;
        update(x), update(father);
    }
    void splay(int x) {
        for (int f = fa[x]; f = fa[x], f; rotate(x)) {
            if (fa[f]) rotate(which(x) == which(f) ? f : x);
        }
        root = x;
    }
    void ins(int k) {
        if (!root) {
            val[++num] = k;
            ++cnt[num];
            root = num;
            update(root);
            return;
        }
        int now = root, f = 0;
        while (1) {
            if (val[now] == k) {
                ++cnt[now];
                update(now), update(f);
                splay(now);
                break;
            }
            f = now, now = son[now][val[now] < k];
            if (!now) {
                val[++num] = k;
                ++cnt[num];
                fa[num] = f;
                son[f][val[f] < k] = num;
                update(num), update(f);
                splay(num);
                break;
            }
        }
    }
    int pre() {
        int now = son[root][0];
        while (son[now][1]) now = son[now][1];
        splay(now); return now;
    }
    int nxt() {
        int now = son[root][1];
        while (son[now][0]) now = son[now][0];
        splay(now); return now;
    }
    int qrank(int k) {
        int ans = 0, now = root;
        while (1) {
            if (k < val[now]) now = son[now][0];
            else {
                ans += size[son[now][0]];
                if (val[now] == k) {
                    splay(now);
                    return ans + 1;
                }
                ans += cnt[now];
                now = son[now][1];
            }
        }
    }
    int qkth(int k) {
        int now = root;
        while (1) {
            if (son[now][0] && k <= size[son[now][0]]) now = son[now][0];
            else {
                k -= size[son[now][0]] + cnt[now];
                if (k <= 0) {
                    splay(now);
                    return val[now];
                }
                now = son[now][1];
            }
        }
    }
    void del(int k) {
        qrank(k);
        if (cnt[root] > 1) {
            --cnt[root];
            update(root);
            return;
        }
        if (!son[root][0] && !son[root][1]) {
            clear(root);
            root = 0;
            return;
        }
        if (!son[root][0]) {
            int now = root;
            root = son[root][1];
            fa[root] = 0;
            clear(now);
            return;
        }
        if (!son[root][1]) {
            int now = root;
            root = son[root][0];
            fa[root] = 0;
            clear(now);
            return;
        }
        int now = root, x = pre();
        fa[son[now][1]] = x;
        son[x][1] = son[now][1];
        clear(now);
        update(root);
    }
}

int main() {
    read(n), read(m);
    for (int i = 1, x; i <= n; ++i) {
        read(x);
        Splay::ins(x);
    }
    for (int i = 1, opt, x; i <= m; ++i) {
        read(opt), read(x);
        x ^= last;
        if (opt == 1) Splay::ins(x);
        else if (opt == 2) Splay::del(x);
        else if (opt == 3) {
            Splay::ins(x);
            last = Splay::qrank(x); 
            ans ^= last;
            Splay::del(x);
        }
        else if (opt == 4) {
            last = Splay::qkth(x);
            ans ^= last;
        }
        else if (opt == 5) {
            Splay::ins(x);
            last = Splay::val[Splay::pre()];
            ans ^= last;
            Splay::del(x);
        }
        else if (opt == 6) {
            Splay::ins(x);
            int last = Splay::val[Splay::nxt()];
            ans ^= last;
            Splay::del(x);
        }
    }
    std::cout << ans << '\n';
    return 0;
}