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.
i = int(input())
if i <= 9: print(i)
else:
    c = 9
    t = 9
    x= 1
    while i > c*10:x +=1; t += (c*10)*x; c*=10
    x +=1
    t += (i-(int('9'*len(str(c)))))*x
    print(t)