Unique Morse Code Words

Problem Description

Given an array of strings words where each word can be written as a concatenation of the Morse code of each letter, return the number of different transformations among all words we have.

Key Insights

• Each letter of the alphabet corresponds to a unique Morse code representation.
• The transformation of a word is the concatenation of the Morse codes of its letters.
• We can use a set data structure to track unique transformations since sets inherently do not allow duplicate values.

Space and Time Complexity

Time Complexity: O(n * m) where n is the number of words and m is the average length of the words.
Space Complexity: O(k) where k is the number of unique Morse code transformations.

Solution

To solve the problem, we will:

1. Create a list that maps each letter (a-z) to its corresponding Morse code.
2. Initialize a set to store the unique Morse code transformations.
3. For each word in the input list:
   • Convert each character of the word to its Morse code using the mapping.
   • Concatenate the Morse codes to form the transformation of the word.
   • Add the transformation to the set.
4. The size of the set will give the number of unique transformations.

Code Solutions