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.
ch=str(input())
n=int(ch)
res=0
if len(ch)>1:
    for i in range(1,len(ch)):
        res+=i*(10**i-10**(i-1))
res+=len(ch)*(n+1-10**(len(ch)-1))
print(res)