Maximum sum

You have two arrays A , B each are N integers and K magic spells. You can use a magic spell to replace Ai with Ai^Bi where ^ is the XOR operation You can use each magic spell on only one element and you can't use more than magic spell on one element You must use all K magic spells as it may explode if you didn't use it. What is the maximum sum of elements inA you can get if you used the mag