804. Unique Morse Code Words

804. Unique Morse Code Words

Question

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:

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

Given an array of strings words where each word can be written as a concatenation of the Morse code of each letter.

  • For example, "cab" can be written as "-.-..--...", which is the concatenation of "-.-.", ".-", and "-...". We will call such a concatenation the transformation of a word.

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

Solution

Code

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class Solution {
public int uniqueMorseRepresentations(String[] words) {
String[] alphabet = new String[]{".-","-...","-.-.","-..",".","..-.","--.",
"....","..",".---","-.-",".-..","--","-.",
"---",".--.","--.-",".-.","...","-","..-",
"...-",".--","-..-","-.--","--.."};
HashSet<String> set = new HashSet<>();

for(String word : words){
StringBuffer sb = new StringBuffer();
for(char c : word.toCharArray()){
sb.append(alphabet[c - 'a']);
}
set.add(sb.toString());
}

return set.size();
}
}
Author

Xander

Posted on

2022-08-17

Updated on

2022-08-17

Licensed under

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