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())
j, p = 1, 0
while 10 * j <= n:
    j *= 10
    p += 1
s, k = 0, 9
for i in range(1, p + 1):
    s += k * i
    k = k * 10
print(s + (p + 1) * (n - j + 1))