Python之设计一个pop、push、top并能在常数时间内检测最小元素的栈

设计一个pop、push、top、getmin操作，并能在常数时间内检测最小元素的栈 class Minstack(object): def init(self): self.stack = [] self.Minstack = [] def isEmpty(self): return len(self.stack)<1 def push(self,item): self.stack.append(item) if self.Minstack == [] or item self.Minstack.append(item) def top(self): if not self.isEmpty(): return self.stack[-1] def getMin(self): if not self.isEmpty(): return self.Minstack[-1] def pop(self): if not self.isEmpty(): if self.Minstack[-1]==self.top(): self.Minstack.pop() self.stack.pop() stack = Minstack() stack.push(-2) stack.push(0) stack.push(-3) stack.push(5) stack.push(-4) print(stack.getMin()) stack.pop() print(stack.top()) print(stack.getMin())