1193. Detect Capital

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:

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

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

您在真实的面试中是否遇到过这个题？   是

样例

Input: "USA"
Output: True

Input: "FlaG"
Output: False

我用了最直接粗暴的方法叫做：分情况考虑

class Solution {
public:
    /**
     * @param word: a string
     * @return: return a boolean
     */
    bool detectCapitalUse(string &word) {
        // write your code here
        if(word[0]-'a'>=0&&word[0]-'a'<26){
            for(int i=1;i<word.length();i++){
                if(word[i]-'a'<0||word[i]-'a'>26) return false;
            }
        }
        else if(word[0]-'A'>=0&&word[0]-'A'<26&&word[1]-'a'>=0&&word[1]-'a'<26){
            for(int i=2;i<word.length();i++){
                if(word[i]-'a'<0||word[i]-'a'>26) return false;
            }
        }
        else if(word[0]-'A'>=0&&word[0]-'A'<26&&word[1]-'A'>=0&&word[1]-'A'<26){
            for(int i=2;i<word.length();i++){
                if(word[i]-'A'<0||word[i]-'A'>26) return false;
            }
        }
        return true;
    }
};