<p>Given an integer array <code>nums</code>, return <em>the sum of divisors of the integers in that array that have exactly four divisors</em>. If there is no such integer in the array, return <code>0</code>.</p>

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

<pre>
<strong>Input:</strong> nums = [21,4,7]
<strong>Output:</strong> 32
<strong>Explanation:</strong> 
21 has 4 divisors: 1, 3, 7, 21
4 has 3 divisors: 1, 2, 4
7 has 2 divisors: 1, 7
The answer is the sum of divisors of 21 only.
</pre>

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

<pre>
<strong>Input:</strong> nums = [21,21]
<strong>Output:</strong> 64
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> nums = [1,2,3,4,5]
<strong>Output:</strong> 0
</pre>

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

<ul>
	<li><code>1 &lt;= nums.length &lt;= 10<sup>4</sup></code></li>
	<li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li>
</ul>

class Solution {
public:
    int sumFourDivisors(vector<int>& nums) {
        vector<bool>arr(100001,1);
        vector<int>primes;

        // cout<<arr.size();
        for(int i=2;i*i<arr.size();i++){
            if(arr[i]){
                // primes.push_back(i);
                for(int j=i*i;j<arr.size();j+=i){
                    arr[j]=0;
                    // if(i>100 && j>1000)cout<<j<<",";

                }
            }
        }
        for(int i=2;i<arr.size();i++){
            if(arr[i])primes.push_back(i);
        }
        // cout<<primes.size();
        int ans=0;
        for(int i :nums){
            map<int,int>mp;
            int cnt=0;
            for(int j:primes){
                int k=i;
                while(k>0 && k%j ==0){
                    mp[j]++;
                    k/=j;
                    // cout<<k<<" "<<j<<endl;
                    cnt++;
                }
            }
            // cout<<i<<" "<<cnt<<endl;
            // for(auto it:mp){
            //     cout<<"divs "<<it.first<<" "<<it.second<<endl;
            // }
            if(mp.size()==1){
                int k=mp.begin()->first;
                if(mp[k]==3){
                    // cout<<"case3 "<<i<<" "<<k<<endl;
                    ans+=1+i+k+ i/k;
                }
            }
            if(mp.size()==2 && cnt==2){
                int k=mp.begin()->first;
                // cout<<"case2 "<<i<<" "<<k<<endl;
                ans+=1+i+k+ i/k;
            }
        }

        return ans;
    }
};
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