Problem9694--ABC188 —— F - +1-1x2

9694: ABC188 —— F - +1-1x2

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

Takahashi has written an integer $X$ on a blackboard. He can do the following three kinds of operations any number of times in any order:

-   increase the value written on the blackboard by $1$;
-   decrease the value written on the blackboard by $1$;
-   multiply the value written on the blackboard by $2$.

Find the minimum number of operations required to have $Y$ written on the blackboard.

Input

Input is given from Standard Input in the following format:

```
$X$ $Y$
```

Output

Print the answer.

Constraints

-   $1 \le X \le 10^{18}$
-   $1 \le Y \le 10^{18}$
-   $X$ and $Y$ are integers.

Sample 1 Input

3 9

Sample 1 Output

3

Initially, 3 is written on the blackboard. The following three operations can make it 9:

  • increase the value by 1, which results in 4;
  • multiply the value by 2, which results in 8;
  • increase the value by 1, which results in 9.

Sample 2 Input

7 11

Sample 2 Output

3

The following procedure can make the value on the blackboard 11:

  • decrease the value by 1, which results in 6;
  • multiply the value by 2, which results in 12;
  • decrease the value by 1, which results in 11.

Sample 3 Input

1000000000000000000 1000000000000000000

Sample 3 Output

0
If the value initially written on the blackboard equals Y, print 0.

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