说明
- combinations方法在组合
- permutations方法在排列
- python2中返回list
eg
zangchuanqideMacBook-Pro:zcq$ python
Python 2.7.16 (default, Apr 1 2019, 14:50:41)
[GCC 4.2.1 Compatible Apple LLVM 10.0.1 (clang-1001.0.46.3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import itertools
>>> list1=list(itertools.combinations('abc',2))
>>> print list1
[('a', 'b'), ('a', 'c'), ('b', 'c')]
>>> list2=list(itertools.permutations('abc',2))
>>> print list2
[('a', 'b'), ('a', 'c'), ('b', 'a'), ('b', 'c'), ('c', 'a'), ('c', 'b')]