Happy new year!

Today I have done leetcode's February LeetCoding Challenge with cpp.

February LeetCoding Challenge 1

Description

Best Time to Buy and Sell Stock

You are given an array prices where prices[i] is the price of a given stock on the ith day.

You want to maximize your profit by choosing a single day to buy one stock and choosing a different day in the future to sell that stock.

Return the maximum profit you can achieve from this transaction. If you cannot achieve any profit, return 0.

Example 1:

Input: prices = [7,1,5,3,6,4]
Output: 5
Explanation: Buy on day 2 (price = 1) and sell on day 5 (price = 6), profit = 6-1 = 5.
Note that buying on day 2 and selling on day 1 is not allowed because you must buy before you sell.

Example 2:

Input: prices = [7,6,4,3,1]
Output: 0
Explanation: In this case, no transactions are done and the max profit = 0.

Constraints:

• 1 <= prices.length <= 105
• 0 <= prices[i] <= 104

Solution

class Solution {
public:
  int maxProfit(vector<int>& prices) {
    int mmin;
    int answer = 0;
    for(auto price : prices) {
      mmin = min(mmin, price);
      answer = max(answer, price - mmin);
    }
    return answer;
  }
};

// Accepted
// 211/211 cases passed (163 ms)
// Your runtime beats 48.73 % of cpp submissions
// Your memory usage beats 90.32 % of cpp submissions (93.3 MB)