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 -*-
"""
Created on Thu Jul 16 09:01:05 2020

@author: Harshal
"""


n=int(input())



ans=0
for l in range(1,11):
    if l==len(str(n)):
        ans+=(n-10**(l-1)+1)*l
    elif l<len(str(n)):
        ans+=(9*10**(l-1))*l
    else:
        break
print(ans)