Simple C++ Solution, 0 ms, 100% faster
class Solution {\npublic:\n    string baseNeg2(int n) {\n        int rem;string k=""; \n        if (n==0)\n            return "0";\n        while(n!=0)\n       
class Solution {\npublic:\n    string baseNeg2(int n) {\n        int rem;string k=""; \n        if (n==0)\n            return "0";\n        while(n!=0)\n        {\n          rem=n%(-2);\n          n/= (-2);\n         if(rem<0)\n         {\n             rem+=2;\n             n+=1;\n         }\n        k=to_string(rem)+k;\n        } \n       return k;     \n    }\n};
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