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=input()
a=[]
a.append(9)
k=8
for i in range(9):
    k=k*10+9
    a.append(int(k))
print(sum(a[:len(n)-1])+int((int(n)-(math.pow(10,len(n)-1))+1)*len(n)))
