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 sys
n = int(input())
a = []
z = 0
if n <= 1000:
    for i in range (1,n+1):
        a.append(i)
        z += len(str(a[i-1]))
else:
    None
print(z)
