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.
s = input()
n = int(s)
d = 0
if len(s) == 1:
    print(n)
else:
    for i in range(len(s)-1):
        d += (i+1)*9*10**i
    d += len(s)*(n-10**(len(s)-1)+1)
    print(d)
