<p>Given a string <code>expression</code> of numbers and operators, return <em>all possible results from computing all the different possible ways to group numbers and operators</em>. You may return the answer in <strong>any order</strong>.</p>

<p>The test cases are generated such that the output values fit in a 32-bit integer and the number of different results does not exceed <code>10<sup>4</sup></code>.</p>

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

<pre>
<strong>Input:</strong> expression = &quot;2-1-1&quot;
<strong>Output:</strong> [0,2]
<strong>Explanation:</strong>
((2-1)-1) = 0 
(2-(1-1)) = 2
</pre>

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

<pre>
<strong>Input:</strong> expression = &quot;2*3-4*5&quot;
<strong>Output:</strong> [-34,-14,-10,-10,10]
<strong>Explanation:</strong>
(2*(3-(4*5))) = -34 
((2*3)-(4*5)) = -14 
((2*(3-4))*5) = -10 
(2*((3-4)*5)) = -10 
(((2*3)-4)*5) = 10
</pre>

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

<ul>
	<li><code>1 &lt;= expression.length &lt;= 20</code></li>
	<li><code>expression</code> consists of digits and the operator <code>&#39;+&#39;</code>, <code>&#39;-&#39;</code>, and <code>&#39;*&#39;</code>.</li>
	<li>All the integer values in the input expression are in the range <code>[0, 99]</code>.</li>
</ul>

class Solution {
public:

vector<int> rec(int start,int end,string &e,vector<vector<vector<int>>>&dp){
    if(!dp[start][end].empty())return dp[start][end];
    vector<int>ans;
    if(start==end){
        ans.push_back(e[start]-'0');
        return ans;
    }
    if(end==start+1 && isdigit(e[start])){
        ans.push_back((e[start]-'0')*10+(e[end]-'0'));
        return ans;
    }
    for(int i=start;i<=end;i++){
        char cur=e[i];
        if(isdigit(cur)){
            continue;
        }
    
        vector<int>left=rec(start,i-1,e,dp);
        vector<int>right=rec(i+1,end,e,dp);
        for(auto j:left){
            for(int k:right){
                switch(cur){
                    case '+':{ans.push_back(j+k);break;}
                    case '-':{ans.push_back(j-k);break;}
                    case '*':{ans.push_back(j*k);break;}
                }
            }
        }
    }
        dp[start][end]=ans;
        return ans;
    }


    vector<int> diffWaysToCompute(string e) {
        vector<vector<vector<int>>>dp(e.length(), vector<vector<int>>(e.length()));
        
        return rec(0,e.size()-1,e,dp);
    }
};
8900