0916. Word Subsets

https://leetcode.com/problems/word-subsets

Description

You are given two string arrays words1 and words2.

A string b is a subset of string a if every letter in b occurs in a including multiplicity.

• For example, "wrr" is a subset of "warrior" but is not a subset of "world".

A string a from words1 is universal if for every string b in words2, b is a subset of a.

Return an array of all the universal strings in words1. You may return the answer in any order.

Example 1:

**Input:** words1 = ["amazon","apple","facebook","google","leetcode"], words2 = ["e","o"]
**Output:** ["facebook","google","leetcode"]

Example 2:

**Input:** words1 = ["amazon","apple","facebook","google","leetcode"], words2 = ["l","e"]
**Output:** ["apple","google","leetcode"]

Example 3:

**Input:** words1 = ["amazon","apple","facebook","google","leetcode"], words2 = ["e","oo"]
**Output:** ["facebook","google"]

Example 4:

**Input:** words1 = ["amazon","apple","facebook","google","leetcode"], words2 = ["lo","eo"]
**Output:** ["google","leetcode"]

Example 5:

**Input:** words1 = ["amazon","apple","facebook","google","leetcode"], words2 = ["ec","oc","ceo"]
**Output:** ["facebook","leetcode"]

Constraints:

• 1 <= words1.length, words2.length <= 104

• 1 <= words1[i].length, words2[i].length <= 10

• words1[i] and words2[i] consist only of lowercase English letters.

• All the strings of words1 are unique.

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