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())
sum = 0
p = 1
while p < n:
    if 10 * p < n:
        sum += (10 * p - p) * len(str(p))
        p *= 10
    else:
        print(sum + ((n - p + 1) * len(str(p))))
        break
