Word Subsets

Return every string in words1 that contains all the letters required by each individual string in words2. Letter order does not matter, but repeated letters do: a requirement of "aa" needs at least two occurrences of a. Check each requirement independently, so different strings in words2 can reuse the same occurrences in a candidate. Return the qualifying strings in any order.

Example 1:

Input: words1 = ["cat","taco","coat","dog"]
words2 = ["at","c"]

Output: ["cat","coat","taco"]

Explanation: "cat", "taco", and "coat" each contain a, t, and c. "dog" does not satisfy either requirement.

Example 2:

Input: words1 = ["ab","aab","aba","aa"]
words2 = ["aa","b"]

Output: ["aab","aba"]

Explanation: The requirements together need two copies of a and one copy of b. Only "aab" and "aba" have enough of both letters.

Example 3:

Input: words1 = ["abc","ab"]
words2 = ["ab","ab"]

Output: ["ab","abc"]

Explanation: Each occurrence of the requirement "ab" is checked independently. Both candidates contain a and b, so repeating the requirement does not require extra copies.

Constraints:

• 1 <= words1.length, words2.length <= 10000
• Each word contains between 1 and 10 lowercase English letters.
• All strings in words1 are distinct.