<p>You are given an integer array <code>cards</code> of length <code>4</code>. You have four cards, each containing a number in the range <code>[1, 9]</code>. You should arrange the numbers on these cards in a mathematical expression using the operators <code>[&#39;+&#39;, &#39;-&#39;, &#39;*&#39;, &#39;/&#39;]</code> and the parentheses <code>&#39;(&#39;</code> and <code>&#39;)&#39;</code> to get the value 24.</p>

<p>You are restricted with the following rules:</p>

<ul>
	<li>The division operator <code>&#39;/&#39;</code> represents real division, not integer division.

	<ul>
		<li>For example, <code>4 / (1 - 2 / 3) = 4 / (1 / 3) = 12</code>.</li>
	</ul>
	</li>
	<li>Every operation done is between two numbers. In particular, we cannot use <code>&#39;-&#39;</code> as a unary operator.
	<ul>
		<li>For example, if <code>cards = [1, 1, 1, 1]</code>, the expression <code>&quot;-1 - 1 - 1 - 1&quot;</code> is <strong>not allowed</strong>.</li>
	</ul>
	</li>
	<li>You cannot concatenate numbers together
	<ul>
		<li>For example, if <code>cards = [1, 2, 1, 2]</code>, the expression <code>&quot;12 + 12&quot;</code> is not valid.</li>
	</ul>
	</li>
</ul>

<p>Return <code>true</code> if you can get such expression that evaluates to <code>24</code>, and <code>false</code> otherwise.</p>

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

<pre>
<strong>Input:</strong> cards = [4,1,8,7]
<strong>Output:</strong> true
<strong>Explanation:</strong> (8-4) * (7-1) = 24
</pre>

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

<pre>
<strong>Input:</strong> cards = [1,2,1,2]
<strong>Output:</strong> false
</pre>

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

<ul>
	<li><code>cards.length == 4</code></li>
	<li><code>1 &lt;= cards[i] &lt;= 9</code></li>
</ul>

class Solution {
public:
    vector<double> findPossiabilities(double a,double b)
    {
        vector<double> finalAns;
        finalAns.push_back(a*b);
        finalAns.push_back(a-b);
        finalAns.push_back(b-a);
        finalAns.push_back(a+b);
        if(abs(a)>FLT_EPSILON)
        {
            finalAns.push_back(b/a);
        }
        if(abs(b)>FLT_EPSILON)
        {
            finalAns.push_back(a/b);
        }
        return finalAns;
    }
    bool getFunction(vector<double>&cards)
    {
        int n=(int)cards.size();
        if(n==1)
        {
            return abs(24-cards[0])<=FLT_EPSILON;
        }
        for(int i=0;i<n;i++)
        {
            for(int j=0;j<n;j++)
            {
                if(i==j)
                {
                    continue;
                }
                double firstNumber=cards[i];
                double secondNumber=cards[j];
                //awesome understood
                vector<double> getAns=findPossiabilities(firstNumber,secondNumber);
                vector<double> emptyArray;
                for(auto &it:getAns)
                {
                   emptyArray.clear();
                   emptyArray.push_back(it);
                   for(int ind=0;ind<n;ind++)
                   {
                      if(ind==i||ind==j)
                      {
                        continue;
                      }
                      emptyArray.push_back(cards[ind]);
                   }
                    if(getFunction(emptyArray))
                    {
                         return true;
                    }
                }
            }
        }
        return false;
    }
    bool judgePoint24(vector<int>& cards) {
        int i,j;
        int cardsLength=cards.size();
        vector<double> arr(cards.begin(),cards.end()); 
        // sort(cards.begin(),cards.emd());
        return getFunction(arr);
    }
};
33711