CF109A.Lucky Sum of Digits

传统题 时间 2000 ms 内存 256 MiB 5 尝试 1 已通过 1 标签

Lucky Sum of Digits

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.

Input

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

Output

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.

Samples

11
47
10
-1

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