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()
correct = 0


# for i in range(1,int(n)+1,1):
#   correct += len(str(i))

# print(correct)


n = int(n)
lower_limit = 1
upper_limit = 10
summi = 0
while True :
  if lower_limit <=n < upper_limit:
    summi += (n - lower_limit +1) *  len(str(lower_limit))
    # print('summi now is', summi )
    break

  summi += (upper_limit - lower_limit) *  len(str(lower_limit))
  # print('summi now is', summi)

  lower_limit *=10
  upper_limit *=10
print(summi)