Detect Capital问题及解法

问题描述：

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:

1. All letters in this word are capitals, like "USA".
2. All letters in this word are not capitals, like "leetcode".
3. Only the first letter in this word is capital if it has more than one letter, like "Google".

Otherwise, we define that this word doesn't use capitals in a right way.

示例：

Input: "USA"Output: True

Input: "FlaG"Output: False

Note: The input will be a non-empty word consisting of uppercase and lowercase latin letters.

问题分析：

我们可以统计单词中小写字母的数目，最后根据小写字母数目来进行判断。

过程详见代码：

class Solution {public:    bool detectCapitalUse(string word) {        if(word.length() < 2) return true;        int lower = 0;        int len = word.length();        for(int i = 0;i < len; i++)        {        if(islower(word[i])) lower++;}if(islower(word[0])) return lower == len;else return lower == len - 1  || lower == 0 ;    }};