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.
import math
N = int(input())

i = 1
ans = 0
while(i<N):
	if(i*10<=N):
		ans+=(math.floor(math.log10(i))+1)*(i*10-i)
		i *= 10
	else:
		ans+=(math.floor(math.log10(i))+1)*(N-i+1)
		i = N
print (ans)