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())
ans = 0
 
for i in range(len(str(n))):
    kek = 9 * (10 ** i)
    if n - kek > 0:
        ans += kek * (i+1)
    else:
        ans += n * (i+1)
    n -= kek
 
print(ans)