Can anyone suggest me the best code for power of 2 in ruby without using any predefined functions/ methods …

# Looking for power of 2 algorithm in ruby? without using any predefined functions

Hello @premila.ande, welcome!

Sorry, actually I didn’t get what you really meant! I mean can you clarify us a bit so we may give your problem a try?

Hi, didn’t get any reply yet.

Anyways, if you want to create a program that check if a number is the power of 2, then:

```
check = ->(n) { Math.log2(n).then { |x| x.to_i == x } }
a === 16 # => true
a === 32 # => true
a === 63 # => false
```

Getting power of 2’s up to a given range:

```
print('Enter max range: ') || puts((1..STDIN.gets.to_i).map { |n| 2 ** n })
```

If it doesn’t answer your question, please comment.