题解 | #【模板】栈#
【模板】栈
https://www.nowcoder.com/practice/104ce248c2f04cfb986b92d0548cccbf
# 创建一个栈类。和两个栈的方法,直接调用法法就好啦,可以有更简单的,但这样更直观
class Stack: def __init__(self): self.stack=[] def push(self,element): self.stack.append(element) def pop(self): if len(self.stack)==0: return "error" else: return self.stack.pop(-1) def top(self): if len(self.stack)==0: return "error" else: return self.stack[-1] num = int(input()) st =Stack() for i in range(num): str_num = input() str_list = str_num.split(" ") if str_list[0]=="push": st.push(int(str_list[1])) elif str_list[0]=="pop": print(st.pop()) else: print(st.top())