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.
def lent(n):
    s = 0
    while n > 0:
        s += 1
        n //= 10
    return s

def summer(a, b):
    s = 0
    for i in range(a, b):
        s += 1
    return s

n = int(input())
a = lent(n)
s = 0
if lent(n) > 1:
    for i in range(a - 1):
        s += summer(10 ** i, 10 ** (i + 1))

    if n > 10 ** (a - 1):
        s += (n % (10 ** (a - 1)) + 1) * a
else:
    s = n
print(s)