class MyStack:
# You can only append to back and read from front
def __init__(self):
self.queue = []
def push(self, x: int) -> None:
# Append to back
self.queue.append(x)
# Read from the front till -1
# Note since we iterate TILL -1, means we keep it "last" at new list
for i in range(len(self.queue) -1):
self.queue.append(self.queue.pop(0))
def pop(self) -> int:
# Last in first Out
return self.queue.pop(0)
def top(self) -> int:
return self.queue[0]
def empty(self) -> bool:
if not self.queue:
return True
return False
# Your MyStack object will be instantiated and called as such:
# obj = MyStack()
# obj.push(x)
# param_2 = obj.pop()
# param_3 = obj.top()
# param_4 = obj.empty()