Author has gone out of the stories about Vasiliy, so here is just a formal task description.

You are given q queries and a multiset A, initially containing only integer 0. There are three types of queries:

  1. "+ x" — add integer x to multiset A.
  2. "- x" — erase one occurrence of integer x from multiset A. It's guaranteed that at least one x is present in the multiset A before this query.
  3. "? x" — you are given integer x and need to compute the value <image>, i.e. the maximum value of bitwise exclusive OR (also know as XOR) of integer x and some integer y from the multiset A.



Multiset is a set, where equal elements are allowed.

Input

The first line of the input contains a single integer q (1 ≤ q ≤ 200 000) — the number of queries Vasiliy has to perform.

Each of the following q lines of the input contains one of three characters '+', '-' or '?' and an integer xi (1 ≤ xi ≤ 109). It's guaranteed that there is at least one query of the third type.

Note, that the integer 0 will always be present in the set A.

Output

For each query of the type '?' print one integer — the maximum value of bitwise exclusive OR (XOR) of integer xi and some integer from the multiset A.

Example

Input

10
+ 8
+ 9
+ 11
+ 6
+ 1
? 3
- 8
? 3
? 8
? 11


Output

11
10
14
13

Note

After first five operations multiset A contains integers 0, 8, 9, 11, 6 and 1.

The answer for the sixth query is integer <image> — maximum among integers <image>, <image>, <image>, <image> and <image>.
from collections import defaultdict
d=defaultdict(lambda:0)
height_of_trie=30

def ins(trie,n,i):
	s=bin(n)[2:]
	s=(height_of_trie-len(s))*'0'+s
	k=0
	for j in s:
		if j=='0':
			if trie[k][0]==-1:
				trie[k][0]=i+1
				trie.append([-1,-1,0])
				i+=1
				k=i
			else:
				k=trie[k][0]
		if j=='1':
			if trie[k][1]==-1:
				trie[k][1]=i+1
				trie.append([-1,-1,1])
				i+=1
				k=i
			else:
				k=trie[k][1]
	return i

def max_xor(trie,n):
    s=bin(n)[2:]
    s=(height_of_trie-len(s))*'0'+s
    k=0
    r=''
    for j in s:
        if j=='0':
            if trie[k][1]!=-1:
                k=trie[k][1]
                r+='1'
            elif trie[k][0]!=-1:
                k=trie[k][0]
                r+='0'
            else:
                return 'some problem'
        else:
            if trie[k][0]!=-1:
                k=trie[k][0]
                r+='0'
            elif trie[k][1]!=-1:
                k=trie[k][1]
                r+='1'
            else:
                return 'some problem'
    return int(r,2)
                
def del_ele(trie,n):
    s=bin(n)[2:]
    s=(height_of_trie-len(s))*'0'+s
    k=0
    node=0
    if trie[0][0]!=-1:
        side=0
    elif trie[0][1]!=-1:
        side=1
    else:
        return 'element not found'
    for j in s:
        if j=='0':
            if trie[k][0]==-1:
                return 'element not found'
            if trie[k][1]!=-1:
                node=k
                side=0
            k=trie[k][0]
        else:
            if trie[k][1]==-1:
                return 'element not found'
            if trie[k][0]!=-1:
                node=k
                side=1
            k=trie[k][1]
    trie[node][side]=-1

trie=[[-1,-1,-1]]
last_node=ins(trie,0,0)
n=int(raw_input())
for i in range(n):
    a,b=raw_input().split()
    if a=="+":
        if d[a]==0:
            d[int(b)]+=1
            last_node=ins(trie,int(b),last_node)
        else:
            d[int(b)]+=1
    if a=="-":
        d[int(b)]-=1
        if d[int(b)]==0:
            del_ele(trie,int(b))
        #print trie
    if a=="?":
        print max_xor(trie,int(b))^int(b)

