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())
ans = 0
x = n
digit = 0
while x != 0:
    digit += 1
    x //= 10
if digit == 1:
    ans = n
else:
    sumx = 0
    for i in range(1, digit):
        ans += (9*(10**(i-1)*i)) 
        sumx += (9*(10**(i-1)))
    ans += (n - sumx)*digit
print(ans)