901. Online Stock Span LeetCode Solution

11 months ago

LeetCode Admin

3 minutes

In this guide, you will get 901. Online Stock Span LeetCode Solution with the best time and space complexity. The solution to Online Stock Span problem is provided in various programming languages like C++, Java, and Python. This will be helpful for you if you are preparing for placements, hackathons, interviews, or practice purposes. The solutions provided here are very easy to follow and include detailed explanations.

Problem Statement
Complexity Analysis
Online Stock Span solution in C++
Online Stock Span solution in Java
Online Stock Span solution in Python
Additional Resources

901. Online Stock Span LeetCode Solution image

Problem Statement of Online Stock Span

Design an algorithm that collects daily price quotes for some stock and returns the span of that stock’s price for the current day.
The span of the stock’s price in one day is the maximum number of consecutive days (starting from that day and going backward) for which the stock price was less than or equal to the price of that day.

For example, if the prices of the stock in the last four days is [7,2,1,2] and the price of the stock today is 2, then the span of today is 4 because starting from today, the price of the stock was less than or equal 2 for 4 consecutive days.
Also, if the prices of the stock in the last four days is [7,34,1,2] and the price of the stock today is 8, then the span of today is 3 because starting from today, the price of the stock was less than or equal 8 for 3 consecutive days.

Implement the StockSpanner class:

StockSpanner() Initializes the object of the class.
int next(int price) Returns the span of the stock’s price given that today’s price is price.

Example 1:

Input
[“StockSpanner”, “next”, “next”, “next”, “next”, “next”, “next”, “next”]
[[], [100], [80], [60], [70], [60], [75], [85]]
Output
[null, 1, 1, 1, 2, 1, 4, 6]

Explanation
StockSpanner stockSpanner = new StockSpanner();
stockSpanner.next(100); // return 1
stockSpanner.next(80); // return 1
stockSpanner.next(60); // return 1
stockSpanner.next(70); // return 2
stockSpanner.next(60); // return 1
stockSpanner.next(75); // return 4, because the last 4 prices (including today’s price of 75) were less than or equal to today’s price.
stockSpanner.next(85); // return 6

Constraints:

1 <= price <= 105
At most 104 calls will be made to next.

Complexity Analysis

Time Complexity:
Space Complexity:

901. Online Stock Span LeetCode Solution in C++

class StockSpanner {
 public:
  int next(int price) {
    int span = 1;
    while (!stack.empty() && stack.top().first <= price)
      span += stack.top().second, stack.pop();
    stack.emplace(price, span);
    return span;
  }

 private:
  stack<pair<int, int>> stack;  // (price, span)
};
/* code provided by PROGIEZ */

901. Online Stock Span LeetCode Solution in Java

class StockSpanner {
  public int next(int price) {
    int span = 1;
    while (!stack.isEmpty() && stack.peek().getKey() <= price)
      span += stack.pop().getValue();
    stack.push(new Pair<>(price, span));
    return span;
  }

  // (price, span)
  private Stack<Pair<Integer, Integer>> stack = new Stack<>();
}
// code provided by PROGIEZ

901. Online Stock Span LeetCode Solution in Python

class StockSpanner:
  def __init__(self):
    self.stack = []  # (price, span)

  def next(self, price: int) -> int:
    span = 1
    while self.stack and self.stack[-1][0] <= price:
      span += self.stack.pop()[1]
    self.stack.append((price, span))
    return span
 # code by PROGIEZ