1 # 关键是匹配模式‘\(([^()]+)\)’匹配括号内无括号的内容，分组和^很巧妙的实现了匹配括号以外的字符
2 import re
3
4 origin = '1 - 2 * ((60-30 + (-40.0/5) * (9-2*5/3+7/3*99/4*2998 +10*568/14)) - (-4*3)/(16-3*2))'
5
6 def jisuan(args):
7 value = eval(args)
8 return value
9 while True:
10 result= re.split('\(([^()]+)\)',origin,1)
11 if len(result)==3:
12 before = result[0]
13 content = result[1]
14 after = result[2]
#上面等价于before，content，after = result
15 r = jisuan(content)
16 new_str = before + str(r) + after
17 origin = new_str
18 else:
19 print(jisuan(origin))
20 break
