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())

if n < 10:
    print(n)
else:
    digits = 0
    temp = n
    while temp != 0:
        temp //= 10
        digits += 1

    res = 9
    for i in range(1, digits - 1):
        t = int('9' * (i + 1))
        res += (t - int('9' * i)) * (i + 1)
        # print(res, t)

    res += (n - int('1' + '0' * (digits - 1)) + 1) * digits
    print(res)
