C + + Tree-parent representation, child representation, parent-child representation __c++

Parent Representations:

#include <iostream>
using namespace std;
Template<typename t>
struct node{
	T _data;
	int parent;
};
Template<typename t>
struct tree{
	node<t> array[100];
	int count;
};
Template<typename t>
void AddNode (T data,int parent,tree<t>& tree) {
	Tree.array[tree.count ]._data=data;
	tree.array[tree.count].parent=parent;
	tree.count++;
}

int main () {
	
	tree<int> tree;
	tree.count=0;
	AddNode (0,-1,tree);

	for (int i=0;i<tree.count;i++) {
		cout<<tree.array[i]._data<< ' <<tree.array[i].parent <<endl;
	}
	return 0;
}

Child representation:

#include <iostream>
using namespace std;
struct child{
	int index;
	child* Next;
struct node{
	int data;
	child* child;
struct tree{
	Node array[100];
	int count;
};

void AddNode (tree& t,int data,int parent) {
	t.array[t.count].data=data;
	t.array[t.count].child=0;
	if (parent>-1) {
		child* ch=new child;
		ch->index=t.count;
		ch->next=0;
		child*& Temp=t.array[parent].child;
		while (temp!=0) {
			temp=temp->next;
		}
		temp=ch;
	}
	t.count++;
}

int main () {tree tree
	;
	tree.count=0;
	AddNode (tree,0,-1);
	
	
	for (int i=0;i<tree.count;i++) {
		cout<<tree.array[i].data<<endl;
	}
	return 0;
}

Parent-Child representation:

#include <iostream>
using namespace std;
struct child{
	int index;
	child* Next;
struct node{
	int data;
	int parent; 
	child* child;
struct tree{
	Node array[100];
	int count;
};

void AddNode (tree& t,int data,int parent) {
	t.array[t.count].data=data;
	t.array[t.count].child=0;
	t.array[t.count].parent=parent;
	if (parent>-1) {
		child* ch=new child;
		ch->index=t.count;
		ch->next=0;
		child*& Temp=t.array[parent].child;
		while (temp!=0) {
			temp=temp->next;
		}
		temp=ch;
	}
	t.count++;
}

int main () {tree tree
	;
	tree.count=0;
	AddNode (tree,0,-1);

	
	for (int i=0;i<tree.count;i++) {
		cout<<tree.array[i].data<<endl;
	}
	return 0;
}