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())
ns=str(n)
l=len(ns)
list1=[9,90,900,9000,90000,900000,9000000,90000000,900000000]
list2=[9,99,999,9999,99999,999999,9999999,99999999]
ans=0
if(n==1000000000):
    for i in range(len(list1)):
        ans+=list1[i]
    print(ans)
else:
    if(l==1):
        print(n)
    else:
        for i in range(l-1):
            ans+=list1[i]
        ans+=(n-list2[l-2])*2
        print(ans)


