Mandeep is pre-final year computer science student. He is called mandy by his friends and is famous for his 'Swag' in whole college. Mandy got pre placement offer from a good company so now he is more focused on how to use his swag traits.

He has N swag traits and come up with a strategy of using them. He select two traits which are closest to each other and use there multiplication result as swag value for that day. As there can be more than one pair mandy should select the pair with maximum product. As mandy is weak in problem solving skills help him finding the swag value he would use that day.

Input:

The first line contains an integer N, the number of swag traits, while the next line contains N space-separated integers, a1,a2,…,aN, representing the values of N swag traits.

Output:

Print the swag value mandy will use that day.

Constraints:

• 2 ≤ N ≤ 100000

• 1 ≤ ai ≤ 10000000