check if two bytes are symmetric

Question

I heard this is a question asked in an interview, given two bytes, return true if they are symmetric

public boolean isSym(Byte firstByte, Byte secondByte);

01101000 and 00010110 are symmetric, but 01100000 and 11000000 are not. need to write the code in Java. Any ideas what is the best way to do so?

There are various ways here to reverse a bit sequence: https://graphics.stanford.edu/~seander/bithacks.html#BitReverseObvious — khelwood, Jul 08 '16 at 11:17

score 2 · Accepted Answer · answered Jul 08 '16 at 11:21

public boolean isSym(Byte firstByte, Byte secondByte)
{

    for (int i = 0; i< 8 ; i++){
        if (bitAt(firstByte, i) != bitAt(secondByte, 7 - i))
            return false;
    }

    return true;
}

public byte bitAt(byte num, int position)
{
   return (byte)((num >> position) & (byte)1);
}

check if two bytes are symmetric

1 Answers1