Best Time to Buy and Sell Stock Easy 0 attempts
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Best Time to Buy and Sell Stock

Easy ArrayTwo Pointers LeetCode

You're given an array prices, where prices[i] holds a stock's price on day i. You may buy the stock on exactly one day and sell it on a later day. Work out the largest profit achievable from this single buy-then-sell transaction, returning 0 if no profitable trade is possible.

Input Format
Implement maxProfit(prices). Inputs below show JavaScript function arguments; there is no stdin parsing.
Output Format
Return the result described in the statement.

Sample Input and Output

Example 1 ยท Run Sample

Input
prices = [7,1,5,3,6,4]
Output
5

Example 2

Input
prices = [7,6,4,3,1]
Output
0
Constraints
  • 1 <= prices.length <= 10^5
  • 0 <= prices[i] <= 10^4
Test Cases (2)
Case 1
Args: [[7,1,5,3,6,4]] Expected: 5
Case 2
Args: [[7,6,4,3,1]] Expected: 0
Topics
ArrayTwo Pointers

Track the minimum price seen so far as you iterate. At each step, compute the profit if you sold today and update the maximum profit accordingly.

javascript
function maxProfit(prices) {
  let minPrice = Infinity;
  let maxProfit = 0;

  for (const price of prices) {
    minPrice = Math.min(minPrice, price);
    maxProfit = Math.max(maxProfit, price - minPrice);
  }

  return maxProfit;
}

Time: O(n) Space: O(1)

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JavaScript