Simple beginer friendly Bit Manipulation approch
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 minChanges(int n, int k) {\n        int changes = 0;\n        \n        for (int i = 0; i < 31; ++i) {\n            int bitN = n & (1 << i);\n            int bitK = k & (1 << i);\n            \n            if (bitK == 0 && bitN != 0) {\n                n ^= (1 << i);\n                changes++;\n            }\n        }\n        \n        return (n == k) ? changes : -1;\n    }\n};\n\n```
['Bit Manipulation', 'C++']