【DP】121.买卖股票的最佳时机

题目

Python

class Solution:
    def maxProfit(self, prices: List[int]) -> int:
        max_profit = 0
        min_price = prices[0]
        for i in range(1, len(prices)):
            max_profit = max(max_profit, prices[i] - min_price)
            min_price = min(min_price, prices[i])

        return max_profit

Java

法1：DP

简单题目

class Solution {
    public int maxProfit(int[] prices) {
        if (prices.length == 1) {
            return 0;
        }
        int min = prices[0], profit = 0;
        for (int i = 1; i < prices.length; ++i) {
            min = Math.min(min, prices[i - 1]);
            profit = Math.max(profit, prices[i] - min);
        }

        return profit;
    }
}