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())
y = n
i = 0
res = 0

while(y > 0 ):
    if y > (9*(10**i) ):
        res += 9*(10**i)*(i+1)
        y -= 9*(10**i)
        i+=1
    else:
        res += y*(i+1)
        y = 0

print(res)
