<p>A <strong>valid encoding</strong> of an array of <code>words</code> is any reference string <code>s</code> and array of indices <code>indices</code> such that:</p>

<ul>
	<li><code>words.length == indices.length</code></li>
	<li>The reference string <code>s</code> ends with the <code>&#39;#&#39;</code> character.</li>
	<li>For each index <code>indices[i]</code>, the <strong>substring</strong> of <code>s</code> starting from <code>indices[i]</code> and up to (but not including) the next <code>&#39;#&#39;</code> character is equal to <code>words[i]</code>.</li>
</ul>

<p>Given an array of <code>words</code>, return <em>the <strong>length of the shortest reference string</strong> </em><code>s</code><em> possible of any <strong>valid encoding</strong> of </em><code>words</code><em>.</em></p>

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

<pre>
<strong>Input:</strong> words = [&quot;time&quot;, &quot;me&quot;, &quot;bell&quot;]
<strong>Output:</strong> 10
<strong>Explanation:</strong> A valid encoding would be s = <code>&quot;time#bell#&quot; and indices = [0, 2, 5</code>].
words[0] = &quot;time&quot;, the substring of s starting from indices[0] = 0 to the next &#39;#&#39; is underlined in &quot;<u>time</u>#bell#&quot;
words[1] = &quot;me&quot;, the substring of s starting from indices[1] = 2 to the next &#39;#&#39; is underlined in &quot;ti<u>me</u>#bell#&quot;
words[2] = &quot;bell&quot;, the substring of s starting from indices[2] = 5 to the next &#39;#&#39; is underlined in &quot;time#<u>bell</u>#&quot;
</pre>

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

<pre>
<strong>Input:</strong> words = [&quot;t&quot;]
<strong>Output:</strong> 2
<strong>Explanation:</strong> A valid encoding would be s = &quot;t#&quot; and indices = [0].
</pre>

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

<ul>
	<li><code>1 &lt;= words.length &lt;= 2000</code></li>
	<li><code>1 &lt;= words[i].length &lt;= 7</code></li>
	<li><code>words[i]</code> consists of only lowercase letters.</li>
</ul>

class trieNode{    
    public:
        unordered_map<char,trieNode*>m;  
        bool isend;
};//Our trie
class Solution {
public:
    trieNode *root;
    int c=0;
    static bool comp(string a,string b){//comparator function to sort our vector of string in a descending order        
        return a.length()>b.length();
    }
    
     trieNode *getNode(){
        trieNode *tmp=new trieNode();
        tmp->isend=false;
        return tmp;
    }
    void insert(string word) {
        if(root==nullptr)
            root=getNode();
        trieNode *tmp=root;
        int m=0;//Using this as a flag to indicate whether a string is being added to our trie or not
        for(int i=word.length()-1;i>=0;i--){//inserting the characters in a reverse order into our trie
            if(tmp->m.find(word[i])==tmp->m.end()){          
                tmp->m[word[i]]=getNode();
                m=1;
            }
            tmp=tmp->m[word[i]];
        }
        if(m!=0){//ONLY IF there is a new word we mark it as an end in the trie and update our counter as the word's length          
            tmp->isend=true;
            c+=word.length()+1;
        }
    }    
    
    int minimumLengthEncoding(vector<string>& words) {
       sort(words.begin(),words.end(),comp);
        for(auto i :words)
            insert(i);        
       
        // cout<<c<<" "<<k;
        return c;
    }
};
47716