class Solution {
public:
    string printBin(double num) {
        string ret = "0.";
        int i = 0;
        while (num && i < 32) {
            num *= 2;
            ret += static_cast<int>(num / 1) + '0';
            if (num >= 1) num -= 1;
            i++;
        }
        if (num) {
            return "ERROR";
        }
        return ret;
    }
};