Best Time to Buy and Sell Stockeasy

public class Main {
    public static int maxProfit(int[] prices) {
        // TODO: find the maximum profit from a single buy/sell
        return 0;
    }

    public static void main(String[] args) {
        System.out.println(maxProfit(new int[]{7, 1, 5, 3, 6, 4})); // 5
        System.out.println(maxProfit(new int[]{7, 6, 4, 3, 1}));     // 0
    }
}