410479: GYM104025 E Equal

Aqua and Hiyori love equal numbers.

Aqua loves two integers $$$x$$$ and $$$y$$$, and she wants to perform some operations to make $$$x$$$ and $$$y$$$ equal. In one step, Aqua can do one of the following operations:

1. $$$x\leftarrow x+1$$$.

2. $$$y\leftarrow y+2$$$.

Now, Hiyori sets a problem to Aqua: What is the minimum number of steps required to make $$$x$$$ and $$$y$$$ equal?

But Aqua is stupid, could you help her?

The first and only line contains two integers $$$x\ (0\leq x\leq 10^9)$$$ and $$$y\ (0\leq y\leq 10^9)$$$.

Output a single integer — the minimum number of operations required to make $$$x$$$ and $$$y$$$ equal.

5 10

5

9 3

3