An abundant number has factors that sum to more than itself; thus 12 is abundant as 1 + 2 + 3 + 4 + 6 = 16 > 12; so is 42 as 1 + 2 + 3 + 6 + 7 + 14 + 21 = 54 > 42.  

Actually, this is an unusual property; write a program that given integers M and N computes the number of abundant numbers between M and N inclusive.

Input

One line of input featuring two integers M and N. M < N < 2³¹.

Output

A single integer on its own line, representing the count of abundant numbers between M and N.

Example

Input:
204 1007

Output:
201