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.
# coding=utf-8
n=int(input())
k=0
for i in  range(1,n+1):
    for j in range(1,10):
        if i//(10**j)!=0:
            k+=1
k=k+n
print(k)
		 		 	   				  			 	 				 		 	