How can I add the resulted strings into an array and eliminate duplicates?

Question

I'm new to fairly new to Javascript and I need some help solving the 804. Unique Morse Code Words - Leetcode problem.

I figured how to search return the morse code by using the index of each letter from a word and using it to concatenate the codes at those specific index in the morse code array. The problem is I can't store the results into an Set array excluding the duplicates and returning the length of the Set array.

var letters = ["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"];
var morseCode = [".-", "-...", "-.-.", "-..", ".", "..-.", "--.", "....", "..", ".---", "-.-", ".-..", "--", "-.", "---", ".--.", "--.-", ".-.", "...", "-", "..-", "...-", ".--", "-..-", "-.--", "--.."];
var words = ["gin", "zen", "gig", "msg"]
var uniqueMorseRepresentations = function(words) {
  for (i = 0; i < words.length; i++) {
    let word = words[i];
    var result = "";
    for (j = 0; j < word.length; j++) {
      let letter = word.charAt(j);
      let index = letters.indexOf(letter);
      result += morseCode[index];
    };
    console.log(result);
  };
};
uniqueMorseRepresentations(words);

The console.log method return the results in 4 separate strings but I don't know how to store them into an array while verifying if there are duplicate.

I'm sorry if the question is sloppy. It's my first one.

Thanks in advance!

Why can't you store the results into a `Set`? Where is your code that tries to do that? — Barmar, Aug 15 '19 at 13:00
You could create an object containing each string, by starting with results = {}, then populate with results["Your string"] = true; This would only allow you to create one entry for each string, then at the end you can iterate through the object with for( let str : results ) {} — SPlatten, Aug 15 '19 at 13:02
Possible duplicate of [Get all unique values in a JavaScript array (remove duplicates)](https://stackoverflow.com/questions/1960473/get-all-unique-values-in-a-javascript-array-remove-duplicates) — VLAZ, Aug 15 '19 at 13:03

score 1 · Answer 1 · edited Aug 15 '19 at 13:01

1

Inside your function, create a Set:

 const resultSet = new Set();

Then when each result is built up (when you log it), add the resulting morse code to that Set:

resultSet.add(result);

Then you can finally return that Set, or its .size.

edited Aug 15 '19 at 13:01

Barmar

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answered Aug 15 '19 at 13:00

Jonas Wilms

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score 0 · Answer 2 · answered Aug 15 '19 at 13:08

I think this should solve your problem. Take an obj, and store the result in that and check if the result is repeating then don't push that result into that array. And the time complexity in this operation would be O(1), so you don't have to worry about it if you want to scale your algorithm.

var letters = ["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"];
var morseCode = [".-", "-...", "-.-.", "-..", ".", "..-.", "--.", "....", "..", ".---", "-.-", ".-..", "--", "-.", "---", ".--.", "--.-", ".-.", "...", "-", "..-", "...-", ".--", "-..-", "-.--", "--.."];
var words = ["gin", "zen", "gig", "msg","gig"]
var array  = [];
var uniqueMorseRepresentations = function(words) {
  let obj = {};
  for (i = 0; i < words.length; i++) {
    let word = words[i];
    var result = "";
    for (j = 0; j < word.length; j++) {
      let letter = word.charAt(j);
      let index = letters.indexOf(letter);
      result += morseCode[index];
    };
    if(!obj[result]){
        obj[result] = result;
        array.push(result);
    }
    console.log(result);
  };
    console.log(array)
};
uniqueMorseRepresentations(words);

Yes, that worked! Thank you for the explanation and for taking the time to actually complete the code. Cheers — Adrian Briciu, Aug 16 '19 at 15:41
Can you please upvote my answer, I am stuck on 31 reputations, needs 50 at least. — ANUPAM CHAUDHARY, Aug 17 '19 at 14:36
I have tried, but it says i have less than 15 reputation, so my vote doesn't change the publicly displayed post score :( — Adrian Briciu, Aug 20 '19 at 05:51
It's fine Adrian, but please whenever you got more than 15 reputations, feel free to upvote :p — ANUPAM CHAUDHARY, Aug 21 '19 at 02:36
For sure, i just returned to review this answer because I need it again. Good luck, good sir :) — Adrian Briciu, Aug 24 '19 at 15:21

How can I add the resulted strings into an array and eliminate duplicates?

2 Answers2