直接解题就行
from typing import List
class Solution:
def calPoints(self, operations: List[str]) -> int:
result_list = []
for item in operations:
if item == '+':
result_list.append(result_list[-1] + result_list[-2])
elif item == 'D':
result_list.append(result_list[-1] * 2)
elif item == 'C':
result_list.pop()
else:
result_list.append(int(item))
return sum(result_list)