(Easy) Unique Morse Code Words LeetCode

Description:

International Morse Code defines a standard encoding where each letter is mapped to a series of dots and dashes, as follows: "a" maps to ".-", "b" maps to "-...", "c" maps to "-.-.", and so on.

For convenience, the full table for the 26 letters of the English alphabet is given below:

[".-","-...","-.-.","-..",".","..-.","--.","....","..",".---","-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-","..-","...-",".--","-..-","-.--","--.."]

Now, given a list of words, each word can be written as a concatenation of the Morse code of each letter. For example, "cba" can be written as "-.-..--...", (which is the concatenation "-.-." + "-..." + ".-"). We'll call such a concatenation, the transformation of a word.

Return the number of different transformations among all words we have.

Example:
Input: words = ["gin", "zen", "gig", "msg"]
Output: 2
Explanation: 
The transformation of each word is:
"gin" -> "--...-."
"zen" -> "--...-."
"gig" -> "--...--."
"msg" -> "--...--."

There are 2 different transformations, "--...-." and "--...--.".

Note:

• The length of words will be at most 100.
• Each words[i] will have length in range [1, 12].
• words[i] will only consist of lowercase letters.

Solution:

class Solution {
    public int uniqueMorseRepresentations(String[] words) {
        
        if(words ==null || words.length ==0){
            
            return 0;
        }
        
        
        String[] map = {".-","-...","-.-.","-..",".","..-.","--.","....","..",".---","-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-","..-","...-",".--","-..-","-.--","--.."};
       
        Set<String> s = new HashSet<String>();
        
        int count =0;
         
        
        for(int i = 0; i<words.length; i++){
             String tmp="";
            for(int j = 0; j<words[i].length(); j++){
                
                
                tmp = tmp+(map[(int)words[i].charAt(j)-97]);
                
              
            }
            
              System.out.println(tmp);
            
            if(!s.contains(tmp)){
                    count++;
                }
            
            
            s.add(tmp);
        }
        
        
        return count;
    }
}