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())
i=10
count=0
c2=0
while True:

    if n>=i:
        count+=9*(i//10)*(len(str(i//10)))
        i*=10

    elif n<i:
        i=i//10

        count+=((n-i)+1)*(len(str(i)))
        break

print(count)
