<p>We are given <code>n</code> different types of <code>stickers</code>. Each sticker has a lowercase English word on it.</p>

<p>You would like to spell out the given string <code>target</code> by cutting individual letters from your collection of stickers and rearranging them. You can use each sticker more than once if you want, and you have infinite quantities of each sticker.</p>

<p>Return <em>the minimum number of stickers that you need to spell out </em><code>target</code>. If the task is impossible, return <code>-1</code>.</p>

<p><strong>Note:</strong> In all test cases, all words were chosen randomly from the <code>1000</code> most common US English words, and <code>target</code> was chosen as a concatenation of two random words.</p>

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

<pre>
<strong>Input:</strong> stickers = [&quot;with&quot;,&quot;example&quot;,&quot;science&quot;], target = &quot;thehat&quot;
<strong>Output:</strong> 3
<strong>Explanation:</strong>
We can use 2 &quot;with&quot; stickers, and 1 &quot;example&quot; sticker.
After cutting and rearrange the letters of those stickers, we can form the target &quot;thehat&quot;.
Also, this is the minimum number of stickers necessary to form the target string.
</pre>

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

<pre>
<strong>Input:</strong> stickers = [&quot;notice&quot;,&quot;possible&quot;], target = &quot;basicbasic&quot;
<strong>Output:</strong> -1
Explanation:
We cannot form the target &quot;basicbasic&quot; from cutting letters from the given stickers.
</pre>

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

<ul>
	<li><code>n == stickers.length</code></li>
	<li><code>1 &lt;= n &lt;= 50</code></li>
	<li><code>1 &lt;= stickers[i].length &lt;= 10</code></li>
	<li><code>1 &lt;= target.length &lt;= 15</code></li>
	<li><code>stickers[i]</code> and <code>target</code> consist of lowercase English letters.</li>
</ul>

class Solution {
public:

// ht aee  ee

// aehhtt

// 

  map<pair<string,int>,int>m;
   int help(vector<string>&stickers,string target, int idx)
   {
    if(target.empty())
    return 0;

    if(idx>=stickers.size())
    return INT_MAX;


    if(m.find({target,idx})!=m.end())
    return m[{target,idx}];


      int op1=help(stickers,target,idx+1);

      string temp=target;

      bool isChange=0;

      for(auto j:stickers[idx])
      {
           
           auto idx=temp.find(j);

           if(idx != string::npos)
           {
              temp=temp.substr(0,idx)+temp.substr(idx+1);
              isChange=1;
           }
      }

      if(isChange)
      {
          int y=help(stickers,temp,idx);

          if(y!=INT_MAX)
          op1=min(op1,1+y);
      }

      return m[{target,idx}]=op1;
   }
    int minStickers(vector<string>& stickers, string target) {
        
        m.clear();
        int res=help(stickers,target,0);

        return res==INT_MAX?-1:res;
    }
};
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