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".
Otherwise, we define that this word doesn't use capitals in a right way.
Example 1:
Input: "USA"
Output: True
Example 2:
Input: "FlaG"
Output: False

很简单的一道题 偷懒不想用函数了。

class Solution {
    public boolean detectCapitalUse(String word) {
        if(word==null||word.length()==0) return false;
        int len =word.length();
        char ch1 = word.charAt(0);
        if(ch1>='A'&&ch1<='Z')
        {
            if(len==1)
                return true;
            char ch2 = word.charAt(1);
            if(ch2>='A'&&ch2<='Z')
            {
                int pos = 1;
                while(pos<len&&(word.charAt(pos)>='A'&&word.charAt(pos)<='Z'))
                pos++;
                if(pos!=len)
                return false;
                return true;
            }
            else if(ch2>='a'&&ch2<='z')
            {
                int pos = 1;
              while(pos<len&&(word.charAt(pos)>='a'&&word.charAt(pos)<='z'))
                  pos++;
              if(pos!=len)
                return false;
            return true;
            }
            else
                return false;
        }
        else if(ch1>='a'&&ch1<='z')
        {
            if(len==1)
                return true;
            int pos = 1;
            while(pos<len&&(word.charAt(pos)>='a'&&word.charAt(pos)<='z'))
                pos++;
            if(pos!=len)
                return false;
            return true;
        }
        else
        {
            return false;
        }
    }
}