Given a string array words, find the maximum value of length(word[i]) * length(word[j]) where the two words do not share common letters. You may assume that each word will contain only lower case letters. If no such two words exist, return 0. Example 1: Given ["abcw", "baz", "foo", "bar", "xtfn", "abcdef"] Return 16 The two words can be "abcw", "xtfn". Example 2: Given ["a", "ab", "abc", "d", "cd", "bcd", "abcd"] Return 4 The two words can be "ab", "cd". Example 3: Given ["a", "aa", "aaa", "aaaa"] Return 0 No such pair of words.

中文意思就是，算了，既然做到这个题，这题的意思大家应该非常明确了，就不献丑翻译，还是老老实实解题。

简单说来，就是一个字符串数组里面，找到两个不含相同字符的字符串，求出它们的乘积之和。

开始看到以为这么简单的遍历题目，直接循环不就可以了么？

在数组里，每一个元素字符串依次和其他的字符串比较，看是不是有字符是共同的，没有则计算两个字符串的长度之和。

讯享网

我写的代码如下：

讯享网class Solution { public: int maxProduct(vector<string>& words) { int maxNum = 0;//两层for循环依次比较字符串,剔除自身与自身的比较 for(auto i = words.begin();i != words.end()&& i != j; i++) { for(auto j = words.begin();j != words.end(); j++) { int count = compare(*i,*j); if(maxNum < count) { maxNum = count; } } } return maxNum; } int compare(string line1,string line2)//比较两个有没有共同的字符，没有则计算长度积 { int flag = 1; int count = 0; for(auto val:line1) { if(line2.find(val) != line2.npos) { flag = 0; } } if(flag) { count = line1.size() * line2.size(); } return count; } };

自定义的测试用例：

[“abcw”,”xyz”,”defg”]
结果是：
16

所以小数据可行。

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