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.
n = int(input())
count = 0
x = 1
y = 1

if len(str(n)) == 1:
    print(n)
else:
    for i in range(len(str(n))-1):
        count = 9 * x * y
        x *= 10
        y += 1  
    print(count + 2*(13 - ((10**(len(str(n))-1))-1)) )                 
      
