Problem Statement

Nukes has an integer that can be represented as the bitwise OR of one or more integers between $A$ and $B$ (inclusive). How many possible candidates of the value of Nukes's integer there are?

Constraints

• $1 ≤ A ≤ B < 2^{60}$
• $A$ and $B$ are integers.

Input

The input is given from Standard Input in the following format:

$A$ $B$

Output

Print the number of possible candidates of the value of Nukes's integer.

Sample Input 1

7
9

Sample Output 1

4

In this case, $A=7$ and $B=9$. There are four integers that can be represented as the bitwise OR of a non-empty subset of {$7$, $8$, $9$}: $7$, $8$, $9$ and $15$.

Sample Input 2

65
98

Sample Output 2

63

Sample Input 3

271828182845904523
314159265358979323

Sample Output 3

68833183630578410