如何在Python中找到最长的字符串？

Question

Something like max(len(s1), len(s2)) will only return the maximum length. But if I actually want to find out which string is longer, and perhaps save it to another string, how is that done? max(s1,s2) seems to return the string with the larger value, but not necessarily the longest.

Note: this has to be done without lists or arrays.

Answer 1

max takes a key function which causes max to take the max key(val) for each val , yet still return the val , to wit:

>>> max("foobar", "angstalot")
'foobar'
>>> max("foobar", "angstalot", key=len)
'angstalot'

Answer 2

只需要一个基于每个字符串长度的简单条件表达式：

longest = s1 if len(s1) > len(s2) else s2

Answer 3

def longest(a, b):
   if len(a) > len(b):
       return a
   return b