from collections import deque

with open('input.txt', 'r') as inp:
        lst = deque()
        n = int(inp.readline())
        for i in range(n):
            m = inp.readline().split()
            if m[0] == '+':
                lst.append(m[1:])
            elif m[0] == '-':
                print(*lst.popleft())
            else:
                lst.insert((len(lst) + 1) // 2, m[1:])