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())
s = 0 
m = n 
c = 0
while(m > 0):
    c += 1 
    m //= 10
p = 1
for i in range(c):
    s += (i + 1) * 9 * p 
    p *= 10 
s -= (c * (p - 1 - n))
print(s)
    