520 Detect Capital

1. Description

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, like "Google".

Given a string word, return true if the usage of capitals in it is right.

 

constraints :

• 1 <= word.length <= 100
• word consists of lowercase and uppercase English letters.

2. Algorithms

Ascii codes of alphabet a - z and A - Z are same as below :

• a - z : 97 - 122
• A - Z : 65 - 90

To fits the above three conditions, the lenght of lowercase should be len(word) or len(word) -1 or 0.

 

1. Start
2. Declare variable named count initialized to 0.
3. Repeat the steps while traversing character of input string.
   
   1. If ascii code of current character is lower case(97 - 122), increment count by 1.
4. If the value of count is len(word) - 1 and ascii code of first value is lower than 90, return True
5. If the value of count is len(word) or 0, return True
6. Else, return False.
7. End

3. Codes

class Solution:
    def detectCapitalUse(self, word: str) -> bool:
        count = 0
        for char in word : 
            if ord(char) >= 97 and ord(char) <= 122 : 
                count += 1
                
        if count == len(word) - 1 and ord(word[0]) <= 90 : 
            return True 
        
        if count == len(word) or count == 0: 
            return True 
        
        return False

4. Conclusion