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 :
    X = n+1- 1
elif n < 100:
    X = 2*(n+1) - 11
elif n < 1000:
    X =  3*(n+1)- 111
elif n < 10000:
    X = 4*(n+1) - 1111
elif n < 100000:
    X =5*(n+1)- 11111
elif n < 1000000:
    X =6*(n+1) - 111111
elif n < 10000000:
    X =  7*(n+1) - 1111111
elif n < 100000000:
    X = 8*(n+1) - 11111111
elif n < 1000000000:
    X = 9*(n+1) - 111111111
else :
    X = 10*(n+1) - 111111111
print(int(X))


    
