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())
size = len(str(n))
ar = [0, 9, 90]
s = 90
ans = 0
cum = 0
for i in range(10):
    s*=10
    ar.append(s)
for i in range(size-1):
    ans+= ar[i+1]*(i+1)
    cum+=ar[i+1]
ans += (n - cum) * size
print(ans)
