121. Best time to Buy and Sell Stock (one) Leetcode problem-solving notes

121. Best time to Buy and Sell Stock

Say you has an array for which the i-th element is the price of a given-stock on day I.

If you were-permitted-to-complete at most one transaction (ie, buy one and sell one share of the stock), design an AL Gorithm to find the maximum profit.

Example 1:

Input: [7, 1, 5, 3, 6, 4]output:5max. difference = 6-1 = 5 (Not 7-1 = 6, as selling-price needs-be-larger than buying price)

Example 2:

Input: [7, 6, 4, 3, 1]output:0in this case, no transaction was done, i.e. Max Profit = 0.

It's like I'm afraid we can't understand it. Two examples are given in fact this topic means to give you an array of the elements of the element I mean the price of the first day of the commodity how to choose the best time to buy and sell goods to maximize profits (only one transaction allowed)

It is no doubt to try to buy the highest when the lowest time to sell the simultaneous buy times must be before the sell time feel a traverse enough to maintain a minimum value

The idea is to iterate from the first element while maintaining the minimum and maximum profit values of a traversed element to facilitate the return benefit

There's a way to get the code out of here. Try to write code in a text editor or directly in the Leetcode code input box without overly relying on tools unless you can find a problem and then use the tool to debug it.

public class Solution {public    int maxprofit (int[] prices) {        int min=integer.max_value;        int profit=0;        for (int i=0;i<prices.length-1;i++) {        min=prices[i]<min?prices[i]:min;        profit= (prices[i+1]-min) >profit?prices[i+1]-min:profit;        }        return profit;}    }

is still a one-off.

Convention See details

can also 2ms O (1) space complexity O (n) time complexity personally think that there is no optimal solution time is shorter than I may be the test case is different here is not to see other people's discuss no need to go to the next question

121. Best time to Buy and Sell Stock (one) Leetcode problem-solving notes