Maximum Product of Word Lengths

一道位操作的好题。

当中的两个操作很好。

public class Solution {    public int maxProduct(String[] words) {        if (words == null || words.length == 0) {            return 0;        }        int[] elements = new int[words.length];        for (int i = 0; i < words.length; i++) {            String word = words[i];            for (int j = 0; j < word.length(); j++) {                elements[i] = elements[i] | (1<<(word.charAt(j) - 'a'));            }        }        int max = 0;        for (int i = 0; i < words.length; i++) {            for (int j = i + 1; j < words.length; j++) {                if ((elements[i] & elements[j]) == 0) {                    max = Math.max(max, words[i].length()*words[j].length());                }            }        }        return max;    }}