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.
# http://codeforces.com/contest/552/problem/B

n = int(input())

res = 0
threshold = 10
temp = 9
count = 1
while True:
    if n >= threshold:
        res += temp * count
        threshold *= 10
        temp *= 10
        count += 1
    else:
        res += (temp - (temp + res - n)) * count
        break

print(res)
