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)
else:
    i = 1
    nd = 0

    while 10**i <= n:
        nd += ((10**i)-(10**(i-1)))*i
        i += 1
        
    nd += (1+n-(10**(i-1)))*(i)
    
    print(nd)