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Problems

Constant sum of digits

Constant sum of digits

Time limit 1 second
Memory limit 128 MiB

Find the amount of two-digit numbers that do not change their sum of digits when multiplying a number by a single-digit integer n (n = 0 .. 9).

Input data

One integer n (0n9).

Output data

Print the required amount of two-digit numbers.

Examples

Input example #1
2
Output example #1
10
Source ІІ stage of All-Ukrainian Olympiad, Zhytomyr region