The number of numbers without 8

During long winter evenings, Lady entertains herself with numbers. She takes the numbers from 1 to n, crosses out any number that includes the digit 8, and counts how many numbers remain. Since n can be quite large and Lady is feeling weary, she seeks your assistance. Your task is to write a program that calculates the number of natural numbers from 1 to n that do not have the digit 8 in their representation.

Input

The input consists of a single line containing the integer n (1 ⩽ n ⩽ 10^18).

Output

The output should be a single number representing the count of natural numbers from 1 to n that do not contain the digit 8 in their notation.

Examples