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())
cur, ans = 1, 0
while cur <= n:
    cur *= 10
    if cur > n:
        ans += (n - cur // 10 + 1) * len(str(cur // 10))
    else:
        ans += (cur - cur // 10) * len(str(cur // 10))
print(ans)
