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.
n = int(input())

len_n = len(str(n))
q = len_n * n
i = 1
ns = 9
while i < len_n:
    q -= ns * (len_n - i)
    i += 1
    ns *= 10

print(q)