Easiest C++ Map Code
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:O(n)\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:O(n)\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\nclass Solution {\npublic:\n    int findMaxK(vector<int>& a) {\n        int i,j,k,ans=INT_MIN;\n        unordered_map<int,int>m;\n        for(auto x : a){\n            if(m.find(-x)!=m.end())\n            ans=max(abs(x),ans);\n\n            m[x]++;\n        }\n        if(ans==INT_MIN)\n        return -1;\n        return ans;\n        \n    }\n};\n```
['Array', 'Hash Table', 'C++']