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())
a = [9,90*2,900*3,9000*4,90000*5,900000*6,9000000*7,90000000*8,900000000*9]
ans = 0
x = len(str(n))
for i in range(x-1):
	ans += a[i]
y = n - 10**(x-1) + 1
ans += y * x
if n < 10:
	ans -= 1
print (ans)