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.
from sys import stdin, stdout
import math

n=int(stdin.readline())
i=0
j=1
ans=0
final=9*pow(10,i)
if(n<=9):
    ans=n
else:
    while(n>final):
        n = n - final
        ans+=final*j
        j+=1
        i+=1
        final = 9 * pow(10, i)
    ans+=n*j
stdout.write(str(ans)+"\n")