Given an infinite stream of integers, nums, design a class to find the kth largest element in a stream.

1-kth-largest-from-stream.js

class KthLargest {
  // constructor to initialize heap and add values in it
  constructor(k, nums) {
    // we add all elements into the heap, and then pop until we have k elements
    // those k elements are k largest elements from the stream,
    // and the minimum of those elements is in the top of the heap,
    // and this is the element we need - the kth largest element
    const heap = new MinHeap(nums);
    while (heap.size() > k) {
      heap.poll();
    }
    this.heap = heap;
  }

  // adds element in the heap
  add(val) {
    this.heap.offer(val);
    // remove element from heap to maintain heap.size === k
    this.heap.poll();
    return this.returnKthLargest();
  }

  // returns kth largest element from heap
  returnKthLargest() {
    return this.heap.peek();
  }
}

export default KthLargest;

2-README.md