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())
res = 0
for i in range(9):
    if n >= 10 ** i:
        if n > (10 ** (i + 1)) - 1:
            res += (9 * 10 ** i) * (i + 1)
        else:
            res += (n - 10 ** i + 1) * (i + 1)
            print(res)
            exit()