Easy C++ Solution
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time 
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```cpp []\nclass Solution {\npublic:\n    vector<vector<int>> findPrimePairs(int n) {\n        if(n==2) return {};\n        vector<int>prime(n+1,0);\n        for(int i=2;i<=n;i++){\n            if(prime[i]==0){\n                for(int j=2*i;j<=n;j+=i){\n                    prime[j]=1;\n                }\n            }\n\n            \n        }\n        vector<int>ans;\n        for(int k=2;k<=n;k++){\n            if(prime[k]==0){\n                ans.push_back(k);\n            }\n        }\n      \n        int i=0;\n        int j=ans.size()-1;\n        \n        vector<vector<int>>vec;\n        while(i<=j){\n            if(ans[i]+ans[j]==n){\n                vec.push_back({ans[i],ans[j]});\n                i++;\n                j--;\n            }\n            else if(ans[i]+ans[j]<n){\n                i++;\n            }\n            else j--;\n        }\n        return vec;\n    }\n};\n```
['C++']