# Problem A

A+B or A-B?

Alice believes that a friendly mid-term contest should start with an $A+B$ problem. But Bob disagrees. To increase creativity, he thinks an $A-B$ problem should be used instead.

To settle the dispute, the contest organizers have decided to use both problems. Given two integers $A$ and $B$, the contestants are required to output the value of $(A+B) \text { or } (A-B)$, where $\text {or}$ is the bitwise OR operator.

However, Alice still thinks her $A+B$ idea is superior. She decides to design the sample input of the problem so that the sample output is identical to $A+B$, that is, $A$ and $B$ satisfies the equality $(A+B) \text { or } (A-B) = A+B$. Furthermore, her choice of $A$ and $B$ should satisfy $L \leq B \leq A \leq R$ for some given range $[L, R]$.

How many possible choices of the pair $(A, B)$ are there?

For example, if $L = 5$ and $R = 7$, then the possible choices are $(5, 5)$, $(6, 5)$, $(6, 6)$, $(7, 6)$, and $(7, 7)$, for a total of 5 choices.

## Input

The only line of input contains two integers $L$ and $R$ $(0 \leq L \leq R \leq 2 \times 10^9)$.

## Output

Output a single integer, the number of possible choices of the pair $(A, B)$ such that $L \leq B \leq A \leq R$ and $(A+B) \text { or } (A-B) = A+B$.

Sample Input 1 | Sample Output 1 |
---|---|

5 7 |
5 |