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.
x=input()
y=len(x)
z=0
for i in range(1,y):
 z=z+9*(10**(i-1))*(i+1)

u=int(x)-int("9"*(y-1))
print(z+u)