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.
from math import log
n = int(input())

order = int(log(n, 10))

r = 0
for o in range(order):
    r += 9 * 10**o * (o + 1)
r += (n - 10**order + 1) * (order + 1)

print(r)
