Java 股票最佳交易时机 LeetCode力扣 复杂度为O(n) 笔试、面试高频

import java.util.Scanner;

public class Main{

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		int array[] = new int[5];
		Scanner in = new Scanner(System.in);
		for(int i = 0; i < 5; i++) {
			array[i] = in.nextInt(); 
		}
		int gap = maxProfit(array);
		System.out.print(gap);
		
	}
	
	// 股票交易最佳时机，采用一次遍历
	// 思路：假设你从一周中选择最低价格那天买入，当天卖出，那么在最低点买入，最高点卖出
	public static int maxProfit(int[] prices) {
		
		int maxProfit = 0; // 最大收益
        int buy = Integer.MAX_VALUE; // 当天购买的价格
        for(int i = 0; i < prices.length; i++){
            if(prices[i] < buy){
                buy = prices[i];
            }else if(prices[i] - buy > maxProfit){
                maxProfit = prices[i] - buy;
            }
        }
        return maxProfit;
    }

}