01trie不过

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;

struct Node{
	ll size;
	Node *lson, *rson;
};

const ll N = 4000005;
ll n;
Node *root;
Node *x, *y;

void New(Node *p) {
	x = new Node(), y = new Node();
	p->lson = x; p->rson = y;
	x->lson = NULL; x->rson = NULL;	
	y->lson = NULL; y->rson = NULL;
	x->size = 0; y->size = 0;
}
/*
void build(int k, Node *fa) {
	if(k > 20) return;
	New(fa);
	build(k+1, fa->lson);
	build(k+1, fa->rson);
	return;
}
*/
void ist(ll m, ll delta) {
	Node *u; u = root;
	for(ll i = 31; i >= 0; i --) {
		ll k = (m>>i) & 1;
		if(u->lson == NULL) New(u); 
		if(k == 0) u = u->lson, u->size += delta;
		else u = u->rson, u->size += delta;
	}
}

ll rnk(ll m) {
	Node *u; u = root; ll x = 0;
	for(ll i = 31; i >= 0; i --) {
		ll k = (m>>i) & 1;
		if(u->lson == NULL) New(u);
		if(k == 1) {
			x += u->lson->size, u = u->rson;
		}
		else u = u->lson;
	}
	return x+1;
}

ll val(int m) {
	Node *u; u = root; ll x = 0;
	for(int i = 31; i >= 0; i --) {
		if(u->lson->size >= m) u = u->lson;
		else m -= u->lson->size, u = u->rson, x |= (1 << i);
	}
	return x;
}

ll pre(int m) {
	return val(rnk(m)-1);
}

ll nxt(int m) {
	return val(rnk(m+1));
}

signed main() {
	scanf("%lld", &n);
	root = new Node(); root->lson = NULL; root->rson = NULL;
	for(int i = 1; i <= n; i ++) {
		ll opt, m;
		scanf("%lld%lld", &opt, &m);
		if(opt == 1) ist(m, 1);
		else if(opt == 2) ist(m,-1);
		else if(opt == 3) printf("%lld\n", rnk(m));
		else if(opt == 4) printf("%lld\n", val(m));
		else if(opt == 5) printf("%lld\n", pre(m));
		else if(opt == 6) printf("%lld\n", nxt(m));
	}
}