Easy to understand
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```\nclass Solution {\npublic:\n    int minImpossibleOR(vector<int>& nums) {\n        int n=nums.size();\n        sort(nums.begin(),nums.end());\n        if(nums[0]!=1)return 1;\n        set<int>st;\n        unordered_map<int,bool>mapp;\n        int x=0;\n        for(auto i:nums){\n             x=x|i;\n             st.insert(x);\n             mapp[i]=1;\n            \n        }\n        for(auto i:st){\n            if(mapp.find(i+1)==mapp.end()){\n                return i+1;\n            }\n        }\n        return -1;\n    }\n};\n```
['C++']