买卖股票的最佳时机—leecode（可以多次交易—贪心算法）

    public static int maxProfit2(int[] prices) {
        if (prices == null || prices.length == 0 || prices.length == 1) {
            return 0;
        }
        int gap = 0;
        int profit = 0;
        for (int i = 0; i < prices.length; i++) {
            if (i + 1 >= prices.length) {
                continue;
            }
            gap = prices[i + 1] - prices[i];    //相邻两天的收益
            if (gap > 0) {                    //如果大于0
                profit += gap;              //加到总收益中
            }
        }
        return profit;
    }