样例过不了，3操作出问题了

#include <bits/stdc++.h>
using namespace std;
const int N = 2e7 + 10, INF = 1e9 + 7;
int n, m, ans = 0, last = 0;
struct Node
{
    int l, r;
    int key;
    int val;
    int cnt;   
    int size;  
} tr[N];

int root = 0, idx;
 
void pushup(int p)
{
    tr[p].size = tr[tr[p].l].size + tr[tr[p].r].size + tr[p].cnt;
}
 
int get_node(int key)
{
    tr[++idx].key = key;
    tr[idx].val = rand();
    tr[idx].cnt = tr[idx].size = 1;
    return idx;
}
 
void build()
{
    get_node(-INF),  get_node(INF);
    root = 0, tr[1].r = 2;
    pushup(root);
}
 
void zig(int &p)
{ 
 	int q = tr[p].l;
    tr[p].l = tr[q].r;
    tr[q].r = p;
    p = q;
    pushup(tr[p].r);
	pushup(p); 
}
 
void zag(int &p)
{
    int q = tr[p].r;
    tr[p].r = tr[q].l;
    tr[q].l = p;
    p = q;
    pushup(tr[p].l);
    pushup(p);
}

void insert(int &p,int key)
{
    if(!p) p = get_node(key);
 	else if (tr[p].key == key)
	{
		tr[p].cnt++;
	}
    else if (tr[p].key > key)
	{
        insert(tr[p].l,key);
        if(tr[tr[p].l].val > tr[p].val) zig(p);
    }
    else
	{
        insert(tr[p].r,key);
        if(tr[tr[p].r].val > tr[p].val) zag(p);
    }
    pushup(p);
}
 
void erase(int &p,int key)
{
    if(!p) return ;
    if(tr[p].key == key)
        if(tr[p].cnt > 1) tr[p].cnt--;
        else if (tr[p].l || tr[p].r)
        {
        	if(!tr[p].r || tr[tr[p].l].val > tr[tr[p].r].val)
			{
                zig(p);
                erase(tr[p].r,key);
            }
            else
            {
                zag(p);
                erase(tr[p].l,key);
            }
		}
		else
		{
			p = 0;
			return ;
		} 
	else if(tr[p].key > key) erase(tr[p].l,key);
    else erase(tr[p].r,key);
    pushup(p);
}
  
int _rank(int p, int key)
{
    if (!p) return 1;//存疑,原为 0 
    if (tr[p].key == key) return tr[tr[p].l].size + 1;
    if (tr[p].key > key)  return _rank(tr[p].l,key);
    return tr[tr[p].l].size + tr[p].cnt + _rank(tr[p].r,key);
}
 
int _key(int p, int rank)
{
    if(!p) return INF;//或为 return 0 
    if(tr[tr[p].l].size >= rank) return _key(tr[p].l,rank);
    if(tr[tr[p].l].size + tr[p].cnt >= rank) return tr[p].key;
    return _key(tr[p].r,rank - tr[tr[p].l].size - tr[p].cnt);
}
 
int prev(int p, int key) 
{
    if(!p) return -INF;
    if(tr[p].key >= key) return prev(tr[p].l,key);
    return max(tr[p].key,prev(tr[p].r,key)); 
}

int next(int p, int key)
{
    if(!p) return INF;
    if(tr[p].key <= key)return next(tr[p].r,key);
    return min(tr[p].key,next(tr[p].l,key));
}
 
int main()
{
	srand(time(NULL));
    scanf("%d%d" , &n, &m);
    build();
    for(int i = 1; i <= n; i++)
    {
    	int cnt;
    	scanf("%d" , &cnt);
    	insert(root, cnt);
	}
    while(m--)
	{
        int op,x;
        scanf("%d%d" , &op, &x);
        x ^= last;
    	if(op == 1)
		{
			insert(root,x);
		}
    	else if(op == 2)
		{
			erase(root,x);
		}
    	else if(op == 3)
		{
			last = (_rank(root,x) - 1);
			ans ^= last;
		}
    	else if(op == 4)
		{
			last = (_key(root,x + 1));
			ans ^= last;
			
		}
    	else if(op == 5)
		{
			last = (prev(root,x));
			ans ^= last;
		}
    	else if(op == 6)
		{
			last = (next(root,x));
			ans ^= last;
		}
//		if(op != 1 && op != 2) cout << "        " << last << endl;
		
    }
    printf("%d" , ans);
    return 0;
}