# Unique Morse Code Words Problem

## Description

LeetCode Problem 804.

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:

``````1
[".-","-...","-.-.","-..",".","..-.","--.","....","..",".---","-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-","..-","...-",".--","-..-","-.--","--.."]
``````

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.

Example 1:

``````1
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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 "--...--.".
``````

Example 2:

``````1
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Input: words = ["a"]
Output: 1
``````

Constraints:

• 1 <= words.length <= 100
• 1 <= words[i].length <= 12
• words[i] consists of lowercase English letters.

## Sample C++ Code

``````1
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class Solution {
public:
int uniqueMorseRepresentations(vector<string>& words) {
vector<string> morse_code = { ".-", "-...", "-.-.", "-..", ".",
"..-.", "--.", "....", "..", ".---", "-.-", ".-..", "--",
"-.", "---", ".--.", "--.-", ".-.", "...", "-", "..-",
"...-", ".--", "-..-", "-.--", "--.." };
unordered_set<string> gen_codes;

for (auto word : words) {
string code = "";
for (auto ch : word)
code += morse_code[ch - 'a'];
gen_codes.insert(code);
}

return gen_codes.size();
}
};
``````