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var StockPrice = function () {
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  // Initialize a Map
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  // Should simply store [timestamp -> value]
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  this.data = new Map();
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  // Initialize Max Heap
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  // Should simply store timestamp as value, and price as priority
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  this.max = new MaxPriorityQueue();
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  // Initialize Min Heap
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  // Should simply store timestamp as value, and price as priority
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  this.min = new MinPriorityQueue();
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  // This is find maximum timestamp i.e. current stock price.
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  this.currentTimestamp = -1;
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};
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/**
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 * @param {number} timestamp
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 * @param {number} price
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 * @return {void}
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 */
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StockPrice.prototype.update = function (timestamp, price) {
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  // Check if its a new timestamp or an update to older
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  this.currentTimestamp = Math.max(this.currentTimestamp, timestamp);
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  // Upsert [Insert or Update value] for price at timestamp
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  this.data.set(timestamp, price);
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  // insert timestamp to the queue with price is priority
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  this.max.enqueue(timestamp, price);
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  this.min.enqueue(timestamp, price);
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};
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/**
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 * @return {number}
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 */
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StockPrice.prototype.current = function () {
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  // get the data with max timestamp from map
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  return this.data.get(this.currentTimestamp);
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};
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/**
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 * @return {number}
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 */
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StockPrice.prototype.maximum = function () {
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  // check the front of max queue
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  // element -> timestamp
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  // priority -> price
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  let { element, priority } = this.max.front();
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  // if priority [i.e. price] is not same latest value, discard it
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  while (priority != this.data.get(element)) {
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    this.max.dequeue();
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    element = this.max.front().element;
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    priority = this.max.front().priority;
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  }
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  // return price
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  return priority;
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};
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/**
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 * @return {number}
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 */
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StockPrice.prototype.minimum = function () {
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  // check the front of max queue
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  // element -> timestamp
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  // priority -> price
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  let { element, priority } = this.min.front();
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  // if priority [i.e. price] is not same latest value, discard it
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  while (priority != this.data.get(element)) {
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    this.min.dequeue();
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    element = this.min.front().element;
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    priority = this.min.front().priority;
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  }
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  // return price
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  return priority;
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};
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/**
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 * Your StockPrice object will be instantiated and called as such:
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 * var obj = new StockPrice()
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 * obj.update(timestamp,price)
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 * var param_2 = obj.current()
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 * var param_3 = obj.maximum()
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 * var param_4 = obj.minimum()
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 */