Vanya got an important task — he should enumerate books in the library and label each book with its number. Each of the *n* books should be assigned with a number from 1 to *n*. Naturally, distinct books should be assigned distinct numbers.

Vanya wants to know how many digits he will have to write down as he labels the books.
The first line contains integer *n* (1 ≤ *n* ≤ 10<sup class="upper-index">9</sup>) — the number of books in the library.
num_books = input()

size = len(num_books)
first_num, second_num = 9, 0

for i in range(1,size):
    second_num = second_num + first_num * i
    first_num = first_num * 10

print(second_num + (int(num_books) - 10 ** (size - 1) + 1) * size)
  		 	   	  					 						 		 		