Size of class

[ankushnandan]

CASE without member

class temp
{
public:

private:

};

int main()
{
temp obj1;
cout<<sizeof(obj1);
return 0;
}

output = 1

CASE with member

class temp
{
public:

private:
int a;             // member variable
};

int main()
{
temp obj1;
cout<<sizeof(obj1);
return 0;
}

output = 4

Why the size of object in case 2 is not 5(int + size of empty class)?