[LeetCode] Best Time to Buy and Sell Stock

This post shares a very simple solution, whose code is rewritten below, just 5 lines :-)

 1 class Solution {
 2 public:
 3     int maxProfit(vector<int>& prices) {
 4         int low = INT_MAX, profit = 0;
 5         for (int price : prices) {
 6             low = min(low, price);
 7             profit = max(profit, price - low);
 8         }
 9         return profit;
10     }
11 };

To give an explanation, suppose we denote p[n] to be the maximum profit we can earn from days 0 to n. Then we have the following DP recursive formula:

p[n + 1] = max(p[n], prices[n + 1] - min_{i = 0, ..., n}prices[i]).

The above code simply computes this formula :-)

转载于:https://www.cnblogs.com/jcliBlogger/p/4548105.html