import java.util.*;


public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可
     * 计算最大收益
     * @param prices int整型一维数组 股票每一天的价格
     * @return int整型
     */
    public int maxProfit (int[] prices) {
        // write code here
        if (prices == null || prices.length == 0) {
            return 0;
        }
        int currentPrices = prices[0];
        int result = 0 ;
        for (int i = 1 ; i < prices.length; i++) {
            //卖出时比买入价格高
            if (currentPrices < prices[i]) {
                result +=  prices[i] - currentPrices;
            }
            currentPrices = prices[i];


        }

        return result;
    }
}