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())
p = n
c = 0
sum = 0
while(1):
    p //= 10
    c += 1
    if p is 0: break
    sum += 9 * (10 ** (c-1)) * (c)
sum += (n -10 ** (c-1) +1) * c
print(sum)