LeetCode - Strings - String Matching in an Array

Given an array of string `words`. Return all strings in `words` which is substring of another word in any order.

String `words[i]` is substring of `words[j]`, if can be obtained removing some characters to left and/or right side of `words[j]`.

Example 1:

```Input: words = ["mass","as","hero","superhero"]
Output: ["as","hero"]
Explanation: "as" is substring of "mass" and "hero" is substring of "superhero".
["hero","as"] is also a valid answer.
```

Example 2:

```Input: words = ["leetcode","et","code"]
Output: ["et","code"]
Explanation: "et", "code" are substring of "leetcode".
```

Example 3:

```Input: words = ["blue","green","bu"]
Output: []```

```class Solution {     public List<String> stringMatching(String[] words) {         Arrays.sort(words, new java.util.Comparator<String>() {             @Override             public int compare(String s1, String s2) {                 return s1.length() - s2.length();             }         });         //System.out.println(Arrays.toString(words));         List<String> subStringList = new ArrayList<String>();         for(int i=0;i<words.length;i++){             String s1 = words[i];             for(int j=i+1;j<words.length;j++){                 String s2 = words[j];                 if(s2.contains(s1)){                     subStringList.add(s1);                     break;                 }             }         }         return subStringList;     } }```