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=input()
l=len(n)
n=int(n)
s="1"
for _ in range(l-1):
    s+="0"
s=int(s)
ans=0
while(l>1):
    temp=n-s+1
    ans+=temp*l
    n-=temp
    l-=1
    s=s//10
print(ans+n)