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())
if len(str(n))==1:
    print(n)
elif len(str(n))==2:
    print(n*2-9)
elif len(str(n))==3:
    print(n*2-8)
elif len(str(n))==4:
    print(n*2-7)
elif len(str(n))==5:
    print(n*2-6)
elif len(str(n))==6:
    print(n*2-5)
elif len(str(n))==7:
    print(n*2-4)
elif len(str(n))==8:
    print(n*2-3)
else:
    print(n*2-2)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    # c=0
    # for i in range(1,n+1):
    #     a=len(str(i))
    #     c=c+a
    # print(c)