char* numberToBinaryString(int n)
{
	bool isLowZero = n < 0;
	n = abs(n);
	char* str = new char[33];
	memset(str, 0, 33);
	unsigned short idx = 0;
	//逆序的方便后面负数原码转补码的时候+1
	while (n != 0)
	{
		str[idx] = 0x30 + n % 2;
		idx++;
		n /= 2;
	}

	size_t len = strlen(str);
	//补全
	size_t d = 31 - len;
	for (size_t i = 0; i < d; i++)
		str[len + i] = 0x30;
	len += d;

	//如果是负数,则用补码表示.负数的补码等于原码取反加1,符号位不变
	if (isLowZero)
	{
		//取反
		for (unsigned short i = 0; i < len; i++)
		{
			if (str[i] == 0x30)
				str[i] += 1;
			else
				str[i] -= 1;
		}
		//加1
		for (unsigned short i = 0; i < len; i++)
		{
			if (str[i] == 0x30)
			{
				str[i] = 0x31;
				break;
			}
			else
			{
				str[i] = 0x30;
				//最后一位还是0x31, 则需要进位
				if (i == (len - 1))
				{
					str[len] = 0x31;
					len++;
				}
			}
		}

		//增加符号位
		str[len] = 0x31;
		len++;
	}

	//翻转
	for (unsigned short i = 0; i < len / 2; i++)
	{
		char t = str[i];
		str[i] = str[len - 1 - i];
		str[len - 1 - i] = t;
	}

	cout << str << endl;

	return str;
}