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.
a = int(input())
saida = 0
while(a > 0):
	tam = len(str(a))
	if tam > 1:
		cont = "9" * (tam-1)
		saida += (a-int(cont))*tam
	else:
		saida += a
		break
	a -= (a-int(cont))
print(saida)