318. Maximum Product of Word Lengths

Total Accepted: 9706 Total Submissions: 24927 Difficulty: Medium
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".

class Solution(object):
def maxProduct(self, words):
"""
:type words: List[str]
:rtype: int
"""
n = len(words)
word_map,len_map = [],[]
for word in words:
word_map += sum(1<<(ord(x)-ord('a')) for x in set(word)),
len_map += len(word),

ans = 0
for i in range(n):
for j in range(i+1,n):
if word_map[i] & word_map[j] == 0:
ans = max( len_map[i]*len_map[j], ans )

return ans