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=10
i=1
while 1:
	if t<n:
		s+=i*(t-1)
		t=t*10
		i+=1
	else:
		t=t//10
		s+=i*(n-t+1)
		break
print(s)