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()
k=int(n)
ans=0
t=0
d=9
c=1
while(True):
    if(k>d):
        ans+=c*(d-t)
        c+=1
        t=d
        d=d*10+9
#        print(ans,c,t,d)
    else:
#        print("HERE:", k,t)
        ans+=(k-t)*c
        break
    
print(ans)
        
    
