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>.
class D: u, v, n = None, None, 0
p = [1 << 30 - j for j in range(31)]
def sub(d, y):
    for j in p:
        d = d.u if y & j else d.v
        d.n -= 1
def add(d, y):
    for j in p:
        if not d.u: d.u, d.v = D(), D()
        d = d.u if y & j else d.v
        d.n += 1
def get(d, y):
    s = 0
    for j in p:
        if y & j:
            if d.v.n:
                d = d.v
                s += j
            else: d = d.u
        else:
            if d.u.n:
                d = d.u
                s += j
            else: d = d.v
    print(s)
d = D()
add(d, 0)
for i in range(int(input())):
    k, x = input().split()
    y = int(x)
    if k == '-': sub(d, y)
    elif k == '+': add(d, y)
    else: get(d, y)