eolymp
Problems

The product of even digits in a number

The product of even digits in a number

Find the product of all even digits in an integer.

Input

One 64-bit integer (the number can be negative).

Output

Print the product of all even digits, or -1 if such digits do not exist.

Time limit 1 second
Memory limit 128 MiB
Input example #1
45123
Output example #1
8