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)
elif n < 100:
    print(9 + (n - 9) * 2)
elif n < 1000:
    print(9 + (n - 9) * 2 + (n - 99) * 3)
elif n < 10000:
    print(9 + (n - 9) * 2 + (n - 99) * 3 + (n - 999) * 4)
elif n < 100000:
    print(9 + (n - 9) * 2 + (n - 99) * 3 + (n - 999) * 4 + (n - 9999) * 5)
elif n < 1000000:
    print(9 + (n - 9) * 2 + (n - 99) * 3 + (n - 999) * 4 + (n - 9999) * 5 + (n - 99999) * 6)
elif n < 10000000:
    print(9 + (n - 9) * 2 + (n - 99) * 3 + (n - 999) * 4 + (n - 9999) * 5 + (n - 99999) * 6 + (n - 999999) * 7)
elif n < 100000000:
    print(9 + (n - 9) * 2 + (n - 99) * 3 + (n - 999) * 4 + (n - 9999) * 5 + (n - 99999) * 6 + (n - 999999) * 7 + (n - 9999999) * 8)
elif n < 1000000000:
    print(9 + (n - 9) * 2 + (n - 99) * 3 + (n - 999) * 4 + (n - 9999) * 5 + (n - 99999) * 6 + (n - 999999) * 7 + (n - 9999999) * 8 + (n - 99999999) * 9)
if n == 1000000000:
    print(9 + (n - 9) * 2 + (n - 99) * 3 + (n - 999) * 4 + (n - 9999) * 5 + (n - 99999) * 6 + (n - 999999) * 7 + (n - 9999999) * 8 + (n - 99999999) * 9 + 10)