Best Time to Buy and Buy Stock

This question is difficult, but I think it is very simple. It seems to be easy.

I only used a variable, and the time complexity is linear. In terms of performance, the time is about MS. Then I will take a look at the discussed version, the guy who found the most votes used the same method as me, except that he defined another variable, but it was useless after definition. Maybe he forgot to delete it.

Public class Solution {public int maxProfit (int [] prices) {if (prices. length = 0 | prices. length = 1) {return 0;} else {int profit = 0; int min = prices [0]; for (int I = 0; I <prices. length; I ++) {if (prices [I] <min) {min = prices [I];} else {if (prices [I]-min> profit) {profit = prices [I]-min ;}} return profit ;}}}

 

Best Time to Buy and Buy Stock