JSFiddle - React, Tailwind, and code Playground

by _sir

HTML

<h3>Take an array and return the number of unique duplicates in it</h3>

<p>
<strong>Your answer should be: </strong>0, 1, 2
</p>
<div id="output"></div>

JavaScript

var arr = [[1, 2, 4],[1, 1, 1, 2, 3],[4, 2, 2, 3, 3, 3]];

var dupes = [];
arr.forEach(function(rec) {
	var copy = rec.slice();
 	var single = [];
  console.log(rec);
  
  copy.forEach(function(item) {
  	if (!single.includes(item)) {
    	single.push(item);
    }
  })
  console.log(single);
})


document.getElementById("output").innerHTML = '';