C不使用printf,将十进制数以二进制形式和十六进制的形式输出

void get2string(int num,char* buffer)
{
	int i = 0;

	for (i = 0; i < 32; ++i)
	{
		buffer[i] = num & (1 << (31 - i));
		buffer[i] = buffer[i] >> (31 - i);
		buffer[i] = buffer[i] == 0 ? '0' : '1';
	}
	buffer[32] = '\0';
}

void get16string(long num, char* buffer)
{
	int i = 0;
	buffer[0] = '0';
	buffer[1] = 'x';
	buffer[10] = '\0';
	char* temp = buffer + 2;

	for (i = 0; i < 8; ++i)
	{
		temp[i] = (char)(num << 4 * i >> 28);
		temp[i] = temp[i] >= 0 ? temp[i] : temp[i] + 16;
		temp[i] = temp[i] < 10 ? temp[i] + 48 : temp[i] + 55;
	}
}

int main()
{
	char buffer[33];
	int a = 4;
	get2string(a, buffer);
	cout << buffer << endl;

	char buffer2[11];
	get16string(a,buffer2);
	cout << buffer2 << endl;

	system("pause");
	return 0;
}