力扣： 剑指 Offer II 005. 单词长度的最大乘积

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