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())
fator = 1
cont = 0

while n > (10 ** fator):
    fator += 1

if fator == 1:
    cont += n
else:
    while fator > 1:
        cont += (n+1-(10**(fator-1)))*fator
        fator -= 1
    cont += 9


print(cont)