leetcode 121. Best Time to Buy and Sell Stock-股市交易

原题链接：121.Best Time to Buy and Sell Stock
【思路】

本题考查动态规划。复杂度为n(O)，在遍历过程中记录最小值min。结果 result 只取决于 result 与 prices[i] - min 中的较大值：

public int maxProfit(int[] prices) {
int result = 0, min = 0x7fff_ffff;
for (int price : prices)
if (price < min) min = price;
else result = Math.max(result, price - min);
return result;
}

198 / 198 test
cases passed. Runtime: 2
ms Your runtime beats 60.20% of javasubmissions.