leetcode 520. Detect Capital
Given a word, you need to judge whether the usage of capitals in it is right or not.
We define the usage of capitals in a word to be right when one of the following cases holds:
- All letters in this word are capitals, like "USA".
- All letters in this word are not capitals, like "leetcode".
- Only the first letter in this word is capital if it has more than one letter, like "Google".
Example 1:
Input: "USA" Output: True
Example 2:
Input: "FlaG" Output: False
Note: The input will be a non-empty word consisting of uppercase and lowercase latin letters.
解法1:
class Solution(object): def detectCapitalUse(self, word): """ :type word: str :rtype: bool """ """ USA=True CN=True C=False? U=False? ""=? usa=True Usa=True uSa=False """ # get first letter: # if first letter is Uppaer case: check all the following letter is Lower case or upper case # if first letter is lower case: check all the following letter is lower case # otherwise, False if word[0].islower(): return all(c.islower() for c in word[1:]) else: return all(c.isupper() for c in word[1:]) or all(c.islower() for c in word[1:])
换一种思维:大写字母个数==0或者==1个(仅为首字母)或者字符串长度!
class Solution(object): def detectCapitalUse(self, word): """ :type word: str :rtype: bool """ upper_cnt = 0 for c in word: if c.isupper(): upper_cnt += 1 return upper_cnt == 0 or (upper_cnt == 1 and word[0].isupper()) or upper_cnt == len(word)