Calling an iterative class function or variable

[angelajean]

Hi all,

I have a problem here that I am not sure how I should go about solving. I am thinking of creating classes that iteratively calls on other classes such that at the end of the day, I can get something like:

Criteria[0].Subcriteria[0].Subcriteria[1].Subcriteria[0].value = a;

So it seems like at first instance, I have a Subcriteria class:

class Subcriteria {

public:

  Subcriteria () {
  };

  unsigned int value;

};

And a Criteria class:

class Criteria {

public:

  Criteria () {
  };

  int value = -1;

};

I then declare an array of the Criteria class:

 Criteria *c;

And I supposedly have a list of x subcriterias under this criteria (assuming 1 first), and another set of y subcriterias under each of the x subcriteria and finally z subcriteria under each of the y subcriteria. So theoretically I should have something like the following to specify the upperbound of the subcriteria:

Criteria[0].Subcriteria[x-1].Subcriteria[y-1].Subcriteria[z-1].value = a;

But now it's starting to look cryptic to me and I realise that I am totally lost. So I was wondering if some kind souls can help provide some directions?

Subsequently, I would need to "move up" from the child to the parent class because the value obtained at the lowest child (i.e. Subcriteria[z]) will be aggregated and stored as the value of the parent (i.e. Subcriteria[y]) and this is repeated until Criteria[0] gets a value from all the children.

So, is there a way in which Subcriteria can also check if it's parent is a Subcriteria or a Criteria class? Tentatively, I stored a value of -1 in the Criteria.value variable because I was thinking along the lines of

if (parent.value = -1) {
  do some parent-related functions
else {
  move up to parent subcriteria and aggregate values
};

Head's spinning already.... :(

Cheers,
Angela

[gpraghuram]

Hi,
I think u are trying to achieve a Binary Tree or a List data structure.
If u want to achieve the samethen your implementation need some change.
The SubCriteria class have to have a self referential pointer to itself like

class Subcriteria {
 
public:
 
  Subcriteria () {
  };
  Subcriteria *Next;
 
  unsigned int value;
 
};

Is this what u need ?

Thanks
Raghuram

[svlsr2000]

Hi all,

I have a problem here that I am not sure how I should go about solving. I am thinking of creating classes that iteratively calls on other classes such that at the end of the day, I can get something like:

Criteria[0].Subcriteria[0].Subcriteria[1].Subcriteria[0].value = a;

So it seems like at first instance, I have a Subcriteria class:

class Subcriteria {
 
public:
 
Subcriteria () {
};
 
unsigned int value;
 
};

And a Criteria class:

class Criteria {
 
public:
 
Criteria () {
};
 
int value = -1;
 
};

I then declare an array of the Criteria class:

 Criteria *c;

And I supposedly have a list of x subcriterias under this criteria (assuming 1 first), and another set of y subcriterias under each of the x subcriteria and finally z subcriteria under each of the y subcriteria. So theoretically I should have something like the following to specify the upperbound of the subcriteria:

Criteria[0].Subcriteria[x-1].Subcriteria[y-1].Subcriteria[z-1].value = a;

But now it's starting to look cryptic to me and I realise that I am totally lost. So I was wondering if some kind souls can help provide some directions?

Subsequently, I would need to "move up" from the child to the parent class because the value obtained at the lowest child (i.e. Subcriteria[z]) will be aggregated and stored as the value of the parent (i.e. Subcriteria[y]) and this is repeated until Criteria[0] gets a value from all the children.

So, is there a way in which Subcriteria can also check if it's parent is a Subcriteria or a Criteria class? Tentatively, I stored a value of -1 in the Criteria.value variable because I was thinking along the lines of

if (parent.value = -1) {
do some parent-related functions
else {
move up to parent subcriteria and aggregate values
};

Head's spinning already.... :(

Cheers,
Angela

Are you looking for something like tree.
I found one more thing
Criteria[0].Subcriteria[0].Subcriteria[1].Subcriteria[0].value = a; if i am right you are trying to have object of Subcriteria inside another object of Subriteria this is not allowed in c++

[angelajean]

Hi,
I think u are trying to achieve a Binary Tree or a List data structure.
If u want to achieve the samethen your implementation need some change.
The SubCriteria class have to have a self referential pointer to itself like

class Subcriteria {
 
public:
 
  Subcriteria () {
  };
  Subcriteria *Next;
 
  unsigned int value;
 
};

Is this what u need ?

Thanks
Raghuram

Hi,

Yes. I think I need a tree, not a binary tree though... but I am not familiar with the implementation of a tree. I know that in a binary tree, there will be *Left and *Right.... but I am not sure about a non-binary tree...

Cheers,
Angela

[angelajean]

Are you looking for something like tree.
I found one more thing
Criteria[0].Subcriteria[0].Subcriteria[1].Subcriteria[0].value = a; if i am right you are trying to have object of Subcriteria inside another object of Subriteria this is not allowed in c++

Oh, actually I just tried something like the following and it seemed to work, although I am not sure if the syntax and method are totally correct:

class Subcriteria {

public:

	Subcriteria () {
	};

	Subcriteria *SubCriteria;

	int value;

};


class Criteria {

public:

	Criteria () {
		value = 1;
	};

public:

	int value;
	Subcriteria *SubCriteria;

};

int main() {

	Criteria *C;
	C = new Criteria[4];
	C[0].SubCriteria = new Subcriteria[2];
	C[1].SubCriteria = new Subcriteria[2];
	C[2].SubCriteria = new Subcriteria[3];
	C[3].SubCriteria = new Subcriteria[3];

	C[0].SubCriteria[0].SubCriteria = new Subcriteria[2];

	C[0].SubCriteria[0].value = 3;
	C[0].SubCriteria[1].value = 6;
	
	C[0].SubCriteria[0].SubCriteria[0].value = 10;
	C[0].SubCriteria[0].SubCriteria[1].value = 20;

This seemed to compile and run without problems. But *assuming* that this is correct, I have another problem with traversal.

If for example, I have values at:

	C[0].SubCriteria[0].SubCriteria[0].value = 10;
	C[0].SubCriteria[0].SubCriteria[1].value = 20;

And I want to store it at:

	C[0].SubCriteria[0].value = [I]sum of the children nodes, i.e. 10 + 20[/I]

Is there an iterative way that I could point back to "parent" of children nodes" such that I can do something like (in pseudocode):

for each node starting from the leaves do {
  calculate sum of all children of parent node;
  assign sum to parent.value;
  repeat for all children nodes until root node;
};

It's now the "calling the parent" part that I am having problems now. And oh, thanks guys for mentioning the "tree" twice. Sometimes I can get so blinded by the problem that I am not able to see the bigger picture of the abstract data type.

Cheers,
Angela

[weaknessforcats]

I think you can avoid this type of coding by using an Observer design pattern.

[angelajean]

I think you can avoid this type of coding by using an Observer design pattern.

Oh, sorry, but what is an observer design pattern? I'm not too familiar with design paradigms... :(

[weaknessforcats]

Check out Design Patterns ISBN 0-201-63361-2 page 293.

You use Observer when an action requires one or more other objects to be notified of the change. For example, a change in the address of a Person object may require that the MailingList and VehcileRegistra tion objects be advised of the change so they can report to their users that you have moved.