With the help of closures, I have done this question. 
So when a function is returned which is using a variable of outer function then the outer variable is not removed from the memory as it can be used later. 
One more imp thing is I have used IIFE because when the compiler will do count(), it should return a value of num. so we need a function that when defined should involve immediately. i.e when the compiler writes count it should be equal to count() so when the compiler does "count()" it means count()() is done which give the value of num.
Here console.log(count()) == () =&gt; {
 return ++num;
 }
console.log(count()()) === val of num.
<pre class="language-javascript"><code class="language-javascript">
// your code here

const count = ( () =&gt; {
 let num = 0;

 const func = () =&gt; {
 return ++num;
 }
 func.reset = () =&gt; {
 num = 0;
 }
 return func;
})();


</code></pre>

Code with Explanation

Please create a function count(), when called it should return how many times it has been called,count.reset() should also implemented. count() // 1 c…

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