这里使用一个Python字符串对象的函数：
| find(...)
| S.find(sub [,start [,end]]) -> int
|
| Return the lowest index in S where substring sub is found,
| such that sub is contained within s[start:end]. Optional
| arguments start and end are interpreted as in slice notation.
|
| Return -1 on failure
1 #_*_coding:utf-8_*_ 2 3 A = "world" ; 4 B = "MaoGuy" ; 5 6 C = "Hello,world.I am MaoGuy!" ; 7 8 result = "" 9 10 if C.find(A): 11 startIndex = C.find(A) 12 if C.find(B) > startIndex: 13 endIndex = C.find(B) + len (B) 14 result = C[startIndex:endIndex] 15 16 print (result)