Implement Queue using Stacks
class MyQueue:
def __init__(self):
self.stk = []
self.stk2 = []
def push(self, x: int) -> None:
self.stk.append(x)
def pop(self) -> int:
if not self.stk2:
while self.stk:
self.stk2.append(self.stk.pop())
return self.stk2.pop()
def peek(self) -> int:
if not self.stk2:
while self.stk:
self.stk2.append(self.stk.pop())
return self.stk2[-1]
def empty(self) -> bool:
return not self.stk and not self.stk2