This problem is a programming version of Problem 32 from projecteuler.net
We shall say that an -digit number is pandigital if it makes use of all the digits to exactly once; for example, the 5-digit number, 15234, is 1 through 5 pandigital.
The product 7254 is unusual, as the identity, 39 × 186 = 7254, containing multiplicand, multiplier, and product is 1 through 9 pandigital.
Find the sum of all products whose multiplicand/multiplier/product identity can be written as a 1 through pandigital.
HINT: Some products can be obtained in more than one way so be sure to only include it once in your sum.
Input contains an integer
Print the answer corresponding to the test case.