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())
cnt=n
if n>9:
	cnt+=n-9
if n>99:
	cnt+=n-99
if n>999:
	cnt+=n-999
if n>9999:
	cnt+=n-9999
if n>99999:
	cnt+=n-99999
if n>999999:
	cnt+=n-999999
if n>9999999:
	cnt+=n-9999999
if n>99999999:
	cnt+=n-99999999
if n>999999999:
	cnt+=n-999999999
print(cnt)