import java.util.*;


public class Solution {
    /**
     * 
     * @param prices int整型一维数组 
     * @return int整型
     */
    public int maxProfit (int[] prices) {
        // write code here
        if(prices.length < 2){
            return 0;
        }
        int maxP = prices[1] - prices[0];
        for(int i =0;i<prices.length - 1;i++){
            int next = prices[i];
            for(int j = i + 1;j<prices.length;j++){
                maxP = Math.max(maxP,(prices[j] - next));
            }
        }
        if(maxP < 0){
            return 0;
        }
        return maxP;
    }
}