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 > 9:
    f = True

    x = round(((n + 1) / 10) - 1, 2)

    t = len(str(n))

    #print(x)
    #print(t)

    m = 9

    while x % 1 != 0 or f:
        f = False
        x *= 10
        m += x * t

    print(int(m))
else:
    print(n)
