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Try the code with "011" or "110" and consider the value of k.
Put the results in three columns, the digit, k and the value of the pow() method

You are confusing the value of a char with the value of an int. The char '1' does not have the save value as the int 1. To see then difference execute this:

System.out.println((int)'1' + " vs "...

Please copy and paste here anything you need help with.
I can't read anything from that image.

Please copy the full text of the error message and paste it here.

You didn't post what the results will be for that input.

A solution would be to convert the binary String to an int and then convert that int to an octal String.
Work on one part at a time.

Can you explain the steps the program must take to do the conversions?
Do them one at a time:
int to octal String

When you have to logic to do that, then do:
int to hexadecimal String

To...

Please explain what the problem with the code is. Post the program's output and add some comments to it to explain what is wrong and show what the output should be.

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