Second Largest Element

You are given a list of integers. Your task is to find the second largest distinct element in the list. If the list has fewer than two distinct elements, output None.

The input consists of an integer n representing the number of elements, followed by a line of n space-separated integers. Your program should print the second largest distinct number, or None if it does not exist.

The formula to describe the problem is as follows:

Let \(A = \{a_1, a_2, \ldots, a_n\}\) be the set of input numbers. If \(|\{a_1, a_2, \ldots, a_n\}| < 2\), output \(None\); otherwise, output the second greatest element in \(\{a_1, a_2, \ldots, a_n\}\).

inputFormat

The first line contains an integer n, the number of elements. The second line contains n space-separated integers.

outputFormat

Print a single line containing the second largest distinct integer, or 'None' if it doesn't exist.## sample

6
4 1 7 3 2 7

4