Maximize Stock Profit

You are given a list of stock prices, where the i-th element represents the price of a given stock on day i. Your task is to compute the maximum profit that can be achieved by buying on one day and selling on a later day. If no profit can be achieved, return 0.

Formally, if you choose to buy at price \(p_{buy}\) and sell at price \(p_{sell}\) with \(sell > buy\), the profit is \(p_{sell} - p_{buy}\). You need to maximize this value.

Input and output: The input is read from stdin and the output is printed to stdout.

inputFormat

The first line contains an integer (n), the number of stock prices. The second line contains (n) space-separated integers representing the stock prices.

outputFormat

Output a single integer representing the maximum profit that can be achieved. If no profit is possible, output 0.## sample

6
7 1 5 3 6 4

5