simple and easy C++ solution 😍❤️‍🔥
\n\n# if it\'s help, please up \u2B06 vote! \u2764\uFE0F\n###### Let\'s Connect on LinkedIn: www.linkedin.com/in/shishirrsiam\n###### Let\'s Connect on Facebook
\n\n# if it\'s help, please up \u2B06 vote! \u2764\uFE0F\n###### Let\'s Connect on LinkedIn: www.linkedin.com/in/shishirrsiam\n###### Let\'s Connect on Facebook: www.fb.com/shishirrsiam\n\n\n# Complexity\n- Time complexity: O(1)\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity: O(1)\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    {\n        int ans = 0;\n        bitset<32>bitN(n), bitK(k);\n        for(int i=0;i<32;i++)\n        {\n            if(bitN[i] and not bitK[i]) ans++;\n            if(not bitN[i] and bitK[i]) return -1;\n        }\n        return ans;\n    }\n};\n```
['Bit Manipulation', 'C++']