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())
pre = 0
now = 9
ans = 0
t = 0
while now < 1000000000:
    t = t + 1
    if min(n, now) < pre:
        break
    ans += (min(n, now) - pre) * t
    pre = now
    now = now * 10 + 9
print(ans)