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var StockSpanner = function () {
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  this.stack = [];
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  this.idx = 0;
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};
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StockSpanner.prototype.next = function (price) {
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  // keep Pop-ing if top element of stack is bigger than current price
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  while (
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    this.stack.length > 0 &&
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    this.stack[this.stack.length - 1][0] <= price
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  ) {
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    this.stack.pop();
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  }
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  // if stack is empty after above operation
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  if (this.stack.length === 0) {
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    // Push current price with index
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    this.stack.push([price, this.idx]);
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    // increment index - this is a tricky part
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    this.idx++;
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    return this.idx;
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  }
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  // caclulate distance from top element of stack and return
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  const res = this.idx - this.stack[this.stack.length - 1][1];
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  this.stack.push([price, this.idx]);
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  this.idx++;
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  return res;
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};