Leetcode buys and sells stocks

Given an array prices , It's the first i Elements prices[i] Represents the number of shares in a given stock i Sky price .

You can only choose One day Buy this stock , And choose A different day in the future Sell the stock . Design an algorithm to calculate the maximum profit you can get .

Return the maximum profit you can make from the deal . If you can't make any profit , return 0 .

Example 1：

Input ：[7,1,5,3,6,4]
Output ：5
explain ： In the 2 God （ Stock price = 1） Buy when , In the 5 God （ Stock price = 6） Sell when , Maximum profit = 6-1 = 5 .
Note that profit cannot be 7-1 = 6, Because the selling price needs to be higher than the buying price ; meanwhile , You can't sell stocks before you buy them .
Example 2：

Input ：prices = [7,6,4,3,1]
Output ：0
explain ： under these circumstances , No deal is done , So the biggest profit is 0.

Tips ：

1 <= prices.length <= 10^5
0 <= prices[i] <= 10^4

java Code ：

class Solution {
    public int maxProfit(int[] prices) {
            int max = 0;
            int minPrice = Integer.MAX_VALUE;
            for(int n:prices) {
                if(n< minPrice) {
                    minPrice = n;
                }else {
                    int diff = n - minPrice;
                    max = Math.max(diff, max);
                }
            }
            return max;
    }
}