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 = int(input())
d = 0
for i in range(1,n+1):
	if i<10:
		d+=1
	elif i<100:
		d+=2
	elif i<1000:
		d+=3
	elif i<10000:
		d+=4
	elif i<100000:
		d+=5
	elif i<1000000:
		d+=6
	elif i<10000000:
		d+=7
	elif i<100000000:
		d+=8
	else:
		d+=9
print(d)					