804. Unique Morse Code Words

🟩 Easy

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:

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

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.

Code

def uniqueMorseRepresentations(self, words: List[str]) -> int:
    english = {'a':".-",'b':"-...",'c':"-.-.",'d':"-..",'e':".",'f':"..-.",'g':"--.",'h':"....",'i':"..",'j':".---",'k':"-.-",'l':".-..",'m':"--",'n':"-.",'o':"---",'p':".--.",'q':"--.-",'r':".-.",'s':"...",'t':"-",'u':"..-",'v':"...-",'w':".--",'x':"-..-",'y':"-.--",'z':"--.."}
    
    morse = set()
    for myword in words:
        morsecode=''
        for c in myword:
            morsecode += english.get(c)
        morse.add(morsecode)
    
    return(len(morse))