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var nthUglyNumber = function (n) {
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  let uglyNo = 1;
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  let uglySet = new Set(); // Set to keep track of all the ugly Numbers to stop repetition
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  uglySet.add(uglyNo);
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  let minHeap = new MinPriorityQueue(); // Javascript provides inbuilt min and max heaps, constructor does not require callback function for primitive types but a comparator callback for object data types, to know which key corresponds to the priority
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  //callback looks like this new MinPriorityQueue((bid) => bid.value)
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  // if this is confusing, check the documentation here
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  // https://github.com/datastructures-js/priority-queue/blob/master/README.md#constructor
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  while (n > 1) {
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    if (!uglySet.has(uglyNo * 2)) {
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      // add only if the set does not have this ugly no.
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      minHeap.enqueue(uglyNo * 2, uglyNo * 2); // enqueue takes two inputs element and priority respectively, both are same here
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      uglySet.add(uglyNo * 2);
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    }
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    if (!uglySet.has(uglyNo * 3)) {
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      minHeap.enqueue(uglyNo * 3, uglyNo * 3);
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      uglySet.add(uglyNo * 3);
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    }
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    if (!uglySet.has(uglyNo * 5)) {
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      minHeap.enqueue(uglyNo * 5, uglyNo * 5);
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      uglySet.add(uglyNo * 5);
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    }
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    uglyNo = minHeap.dequeue().element; //dequeue returns an object with two properties priority and element
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    n--;
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  }
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  return uglyNo;
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};