Remove Duplicates from an Array

Write a function that removes duplicate elements from an array.

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Instructions

Write a function that receives an array of numbers and returns an array with the duplicate elements removed.

For example, if the input is [1,2,3,1,2,3], the output should be [1,2,3].

Tests

0/4

Function Call:

Expected:

removeDuplicates([1,2,3])

[ 1, 2, 3 ]

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removeDuplicates([1,1,1,1])

[ 1 ]

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removeDuplicates([])

[]

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Hidden Test

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See Solution

const removeDuplicates = (myArray) => {
   return Array.from(new Set(myArray))
}

Explanation

We use the Set object to store unique values of any type.
We then convert the Set object to an array using the Array.from method.

Complexity Analysis

The time complexity for this solution is O(n) where n is the length of the input array.

Alternative

For loop

function removeDuplicates(myArray) {
      let uniqueArray = [];
      for (let i = 0; i < myArray.length; i++) {
         if (uniqueArray.indexOf(myArray[i]) === -1) {
               uniqueArray.push(myArray[i]);
         }
      }
      return uniqueArray;
}

Spreading

function removeDuplicates(myArray) {
    return [...new Set(myArray)];
}

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