Given a string of numbers and operators, return all possible results from computing all the different possible ways to group numbers and operators. The valid operators are +, - and *.
给定一系列数字和运算符，通过计算所有不同的组编号和运算符的方式返回所有可能的结果。 有效的运算符是+， - 和*。
Example 1:
Input: "2-1-1"
Output: [0, 2]
Explanation:
((2-1)-1) = 0
(2-(1-1)) = 2
Example 2:
Input: "2*3-4*5"
Output: [-34, -14, -10, -10, 10]
Explanation:
(2*(3-(4*5))) = -34
((2*3)-(4*5)) = -14
((2*(3-4))*5) = -10
(2*((3-4)*5)) = -10
(((2*3)-4)*5) = 10
python实践
#!/usr/bin/env python
# _*_ coding:utf-8 _*_
class Solution(object):
def diffWaysToCompute(self, input):
"""
:type input: str
:rtype: List[int]
"""
result = []
# print(input[1])
# print(input[0:])
# print(input[:2])
# print(len(input))
length = len(input)
ch = ['*', '-', '+']
for i in range(length):
if input[i] in ['*', '-', '+']:
left = self.diffWaysToCompute(input[:i])
right = self.diffWaysToCompute(input[i+1:])
for l in left:
for r in right:
if input[i] == "+":
result.append(l+r)
elif input[i] == "*":
result.append(l*r)
elif input[i] == "-":
result.append(l-r)
if not result:
result.append(int(input))
return result
if __name__ == '__main__':
input = "2*3-4*5"
Solution().diffWaysToCompute(input)
