9.5位操作（2）——给定一个介于0和1之间的实数，类型为double，打印它的二进制表示

//将数字乘以2以后，与1比较。
	public static String printBinary(double num){
		if(num>=1||num<=0)
			return "ERROR";
		StringBuilder binary=new StringBuilder();
		binary.append(".");
		while(num>0){
			if(binary.length()>=32)
				return "ERROR";
			double r=num*2;
			if(r>=1){
				binary.append("1");
				num=r-1;
			}else{
				binary.append("0");
				num=r;
			}
		}
		return binary.toString();
	}

//将数字与0.5比较
	public static String printBinary2(double num){
		if(num>=1||num<=0)
			return "ERROR";
		StringBuilder binary=new StringBuilder();
		double frac=0.5;
		binary.append(".");
		while(num>0){
			if(binary.length()>32){
				return "ERROR";
			}
			
			if(num>=frac){
				binary.append("1");
				num-=frac;
			}else{
				binary.append("0");
			}
			frac/=2;
		}
		return binary.toString();
	}

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