PROGRAMMING:Is this a power of two?

Define a method ispower in the class tool. For the parameter num (Num > 0), judge whether num is a power of 2. If it is, return true; otherwise, return false
In the Main class, we call this method in the main method, enter an integer greater than 0, call the isPower method, if it is the power of 2, output yes, otherwise output the no input if it is 0 or less than 0 integers, output error
###Input format:
Enter an integer, such as 5
###Output format:
Output results such as No
###Input example:
Here is a set of inputs. For example:
```in
fifteen
```
```in
eight
```
```in
-4
```
###Output example:
The corresponding output is given here. For example:
```out
no
```
```out
yes
```
```out
error
```






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