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.
'''	
		Competitive programing
	   Name: Đào Xuân Hoàng Tuấn (Salmon1)
Nothing is impossible, as you as you believe you can do it
		 You can do it!!!
'''
a = input()
n = len(a)
ans = 0;

for i in range(1, n):
	ans += 9*(10**(i-1))*i
	# print(ans)
if n > 1:
	if n == 2:
		ans += (int(a) - 9*(10**(n-2)))*n
	else:
		ans += (int(a) - (9*(10**(n-2)))-9)*n
	# print(ans)
else:
	ans = a
print(ans)
