Javascript Solution [Runtime: 52 ms]
\nvar baseNeg2 = function(N) {\n    if (!N) return "0"\n    let result = ""\n    while (N !== 0) {\n        var remainder = N % -2;\n\n        N = ~~(N / -2) //
```\nvar baseNeg2 = function(N) {\n    if (!N) return "0"\n    let result = ""\n    while (N !== 0) {\n        var remainder = N % -2;\n\n        N = ~~(N / -2) //Math.floor() actually\n        \n        if (remainder < 0) \n\t\t{\n\t\t\tremainder += 2;\n\t\t\tN += 1;\n\t\t}\n        \n        result = remainder + result\n    }\n    return result\n};\n```
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