全RE了，平衡树写的没问题

#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;

const int maxn = 1e5 + 10;
int n, m, x, op, ans, tot, root, last;
struct npde {
	int l, r, rd, val, size;
} t[maxn];
void push_up(int now) {
	t[now].size = t[t[now].l].size + t[t[now].r].size + 1;
	return ;
}
void spilt(int now, int key, int &x, int &y) {
	if (now) {
		if (t[now].val <= key) {
			x = now;
			spilt(t[now].r, key, t[now].r, y);
		} else {
			y = now;
			spilt(t[now].l, key, x, t[now].l);
		}
		push_up(now);
	} else x = y = 0;
	return ;
}
int merge(int x, int y) {
	if (x && y) {
		if (t[x].rd <= t[y].rd) {
			t[x].r = merge(t[x].r, y);
			push_up(x);
			return x;
		} else {
			t[y].l = merge(x, t[y].l);
			push_up(y);
			return y;
		}
	}
	return x + y;
}
int new_node(int key) {
	tot++;
	t[tot].l = t[tot].r = 0;
	t[tot].val = key;
	t[tot].size = 1;
	t[tot].rd = rand();
	return tot;
}
void insert(int key) {
	int x, y;
	spilt(root, key, x, y);
	root = merge(merge(x, new_node(key)), y);
	return ;
}
void del(int key) {
	int x, y, z;
	spilt(root, key, x, y);
	spilt(x, key - 1, x, z);
	z = merge(t[z].l, t[z].r);
	root = merge(merge(x, z), y);
	return ;
}
int get_rank(int key) {
	int x, y;
	spilt(root, key - 1, x, y);
	int ans = t[x].size + 1;
	root = merge(x, y);
	return ans;
}
int get_key(int now, int k) {
	int cnt = t[t[now].l].size + 1;
	if (cnt == k) return t[now].val;
	else if (cnt < k) return get_key(t[now].r, k - cnt);
	return get_key(t[now].l, k);
}
int pre(int key) {
	int x, y;
	spilt(root, key - 1, x, y);
	int ans = get_key(x, t[x].size);
	root = merge(x, y);
	return ans;
}
int next(int key) {
	int x, y;
	spilt(root, key, x, y);
	int ans = get_key(y, 1);
	root = merge(x, y);
	return ans;
}
int main() {
	scanf("%d %d", &n, &m);
	for (int i = 1; i <= n; i++) {
		scanf("%d", &x);
		insert(x);
	}
	for (int i = 1; i <= m; i++) {
		scanf("%d %d", &op, &x);
		x ^= last;
		if (op == 1) insert(x);
		else if (op == 2) del(x);
		else if (op == 3) last = get_rank(x);
		else if (op == 4) last = get_key(root, x);
		else if (op == 5) last = pre(x);
		else last = next(x);
		if (op == 3 || op == 4 || op == 5 || op == 6) ans ^= last;
	}
	printf("%d\n", ans);
	return 0;
}