题解 | #【模板】栈#
【模板】栈
https://www.nowcoder.com/practice/104ce248c2f04cfb986b92d0548cccbf
# 读取输入的操作次数 n = int(input().strip()) # 初始化栈 stack = [] # 处理每个操作 for _ in range(n): operation = input().strip().split() if operation[0] == 'push': # push 操作,将元素入栈 x = int(operation[1]) stack.append(x) elif operation[0] == 'pop': # pop操作,将元素出栈 if stack: print(stack.pop()) else: print('error') elif operation[0] == 'top': # top 操作,输出栈顶,栈顶不出栈 if stack: print(stack[-1]) else: print('error')