You may declare instances of that class.
class{public: int x;} xaaa1, xbbb1, xccc1;
class{public: int y;} xaaa2, xbbb2, xccc2;
int main()
{
xaaa1.x = 1;
xaaa2.y = 2;
xbbb2.y = 3;
cout<< "xaaa1.x = "<< xaaa1.x<< "; xaaa2.y = "<< xaaa2.y
<< "; xbbb2.y = "<< xbbb2.y<< "; xaaa1.x + xaaa2.y + xbbb2.y = "
<< xaaa1.x + xaaa2.y + xbbb2.y<< endl;
You are not obligated to instanciate the class.
For instance, this is not a problem:
class bazz{} a;
int main()
{
bazz b;
bazz;
int;