<p>Given an array of strings <code>words</code> (<strong>without duplicates</strong>), return <em>all the <strong>concatenated words</strong> in the given list of</em> <code>words</code>.</p>

<p>A <strong>concatenated word</strong> is defined as a string that is comprised entirely of at least two shorter words (not necessarily distinct)&nbsp;in the given array.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> words = [&quot;cat&quot;,&quot;cats&quot;,&quot;catsdogcats&quot;,&quot;dog&quot;,&quot;dogcatsdog&quot;,&quot;hippopotamuses&quot;,&quot;rat&quot;,&quot;ratcatdogcat&quot;]
<strong>Output:</strong> [&quot;catsdogcats&quot;,&quot;dogcatsdog&quot;,&quot;ratcatdogcat&quot;]
<strong>Explanation:</strong> &quot;catsdogcats&quot; can be concatenated by &quot;cats&quot;, &quot;dog&quot; and &quot;cats&quot;; 
&quot;dogcatsdog&quot; can be concatenated by &quot;dog&quot;, &quot;cats&quot; and &quot;dog&quot;; 
&quot;ratcatdogcat&quot; can be concatenated by &quot;rat&quot;, &quot;cat&quot;, &quot;dog&quot; and &quot;cat&quot;.</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> words = [&quot;cat&quot;,&quot;dog&quot;,&quot;catdog&quot;]
<strong>Output:</strong> [&quot;catdog&quot;]
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= words.length &lt;= 10<sup>4</sup></code></li>
	<li><code>1 &lt;= words[i].length &lt;= 30</code></li>
	<li><code>words[i]</code> consists of only lowercase English letters.</li>
	<li>All the strings of <code>words</code> are <strong>unique</strong>.</li>
	<li><code>1 &lt;= sum(words[i].length) &lt;= 10<sup>5</sup></code></li>
</ul>

struct Node{
    Node* ch[26];
    bool end;
};
class Trie{
public:
    Node* root;
    Trie(){
        root= new Node();
    }
    void insert(string s){
        Node* temp= root;
        for(auto c: s){
            int t= c-'a';
            if(temp->ch[t]==NULL) temp->ch[t]= new Node();
            temp= temp->ch[t];
        }
        temp->end=true;
    }

    bool search(Node* temp, int idx, int cnt, string &word){
        if(temp==NULL) return false;
        if(idx==word.size()) return cnt>=1 && temp->end;
        
        if(temp->end){
            if(search(root, idx, cnt+1, word)) return true;
        }
        return search(temp->ch[word[idx]-'a'], idx+1, cnt, word);
    }
};


class Solution {
public:
    vector<string> findAllConcatenatedWordsInADict(vector<string>& words) {
        Trie trie;
        for(auto &s: words) reverse(s.begin(), s.end());
        
        for(auto w: words) {
            trie.insert(w);
        }
        vector<string> ans;
        for(auto w: words){
            if(trie.search(trie.root, 0, 0, w)) {
                reverse(w.begin(), w.end());
                ans.push_back(w);
            }
        }
        
        return ans;
    }
};
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