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.
#B. Vanya and Books

n = int(input())

def Potenz(x):
    i = 9
    while(x < 10**i):
        i = i - 1
    return i

Remainder = n - 10**Potenz(n)
Ergebniss = Remainder * (Potenz(n)+1)





for i in range(0, Potenz(n)):
    Ergebniss = Ergebniss + (10**(i+1)-10**i) * (i+1)

print(Ergebniss+Potenz(n)+1)