Petya loves lucky numbers. We all know that lucky numbers are the positive integers whose decimal representations contain only the lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not. Petya wonders eagerly what minimum lucky number has the sum of digits equal to n . Help him cope with the task.

输入描述:

The single line contains an integer n (1 ≤ n ≤ 106) — the sum of digits of the required lucky number.

输出描述:

Print on the single line the result — the minimum lucky number, whose sum of digits equals n. If such number does not exist, print -1.