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=input()
k=len(n)
n=int(n)
sum1=0
for i in range(0,k):
  if(10**(i+1)<=n):
    sum1=sum1+(10**i)*9
  else:
    sum1=sum1+((n-(10**i)+1))*(i+1)
print(sum1)
  