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,m=map(int,input().split())
i=0
while m>n:
    if m%2==0:
        m=m//2
    else:
        m=m+1
    i=i+1
if n>m:
    i=i+(n-m)
print(i)