leetcode 804. Unique Morse Code Words

Seawolf

1. 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.
   
2. 
   
3. For convenience, the full table for the 26 letters of the English alphabet is given below:
   
4. 
   
5. [".-","-...","-.-.","-..",".","..-.","--.","....","..",".---","-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-","..-","...-",".--","-..-","-.--","--.."]
   
6. 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.
   
7. 
   
8. Return the number of different transformations among all words we have.
   
9. 
   
10. Example:
    
11. Input: words = ["gin", "zen", "gig", "msg"]
    
12. Output: 2
    
13. Explanation:
    
14. The transformation of each word is:
    
15. "gin" -> "--...-."
    
16. "zen" -> "--...-."
    
17. "gig" -> "--...--."
    
18. "msg" -> "--...--."
    
19. 
    
20. There are 2 different transformations, "--...-." and "--...--.".
    
21. Note:
    
22. 
    
23. The length of words will be at most 100.
    
24. Each words[i] will have length in range [1, 12].
    
25. words[i] will only consist of lowercase letters.

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1. class Solution {
   
2.     public int uniqueMorseRepresentations(String[] words) {
   
3.         Set <String> map = new HashSet<>();
   
4.         String[] mo = {".-","-...","-.-.","-..",".","..-.","--.","....","..",".---","-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-","..-","...-",".--","-..-","-.--","--.."};
   
5.         for(String i: words){
   
6.             StringBuilder a = new StringBuilder();
   
7.             for(int j =0 ; j < i.length(); j++){
   
8.                
   
9.                 a.append(mo[i.charAt(j) - 'a']);
   
10.             }
    
11.             map.add(a.toString());
    
12.         }
    
13.         
    
14.         return map.size();
    
15.     }
    
16. }

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