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())
m = n
i = 0
cnt = 0
while m//10:
    cnt += (9*(10)**i)*(i+1)
    i += 1
    m //= 10

cnt += (n-10**i+1)*(i+1)

print(cnt)
