Wonderful!

A number is called wonderfully-prime if it is a prime number (only divisible by itself and 1), and when its digits are reversed, the resulting number is also prime. Your task is to output the K-th wonderfully-prime number. If this number exceeds 10^6, output -1.

Input

The input consists of a single integer K (1 ≤ K ≤ 1000).

Output

The output should be a single integer, which is the answer to the problem.

Examples