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())
s=0
t=9
i=1
while t<n:
	s+=i*t
	i+=1
	t=t*10
if t==n:
	s+=i
else:
	z=int(max('0',('9'*(i-1))))
	s+=i*(n-z)
print(s)
	