class Solution:
    def __init__(self):
        self.stack=[]
        self.queue=[]
    def pushCharacter(self,x):
        self.stack.append(x)
    def enqueueCharacter(self,x):
        self.queue.insert(0,x)
    def popCharacter(self):
        return self.stack.pop()
    def dequeueCharacter(self):
        return self.queue.pop()