C++ Programming Code Examples
C++ > Computer Graphics Code Examples
Program to Perform Inorder Recursive Traversal of a Given Binary Tree
/* Program to Perform Inorder Recursive Traversal of a Given Binary Tree */
# include <iostream>
# include <cstdlib>
using namespace std;
/* Node Declaration */
struct node
{
int info;
struct node *left;
struct node *right;
}*root;
/* Class Declaration */
class BST
{
public:
void insert(node *, node *);
void inorder(node *);
void display(node *, int);
BST()
{
root = NULL;
}
};
/* Main Contains Menu */
int main()
{
int choice, num;
BST bst;
node *temp;
while (1)
{
cout<<"-----------------"<<endl;
cout<<"Operations on BST"<<endl;
cout<<"-----------------"<<endl;
cout<<"1.Insert Element "<<endl;
cout<<"2.Inorder Traversal"<<endl;
cout<<"3.Display"<<endl;
cout<<"4.Quit"<<endl;
cout<<"Enter your choice : ";
cin>>choice;
switch(choice)
{
case 1:
temp = new node;
cout<<"Enter the number to be inserted : ";
cin>>temp->info;
bst.insert(root, temp);
break;
case 2:
cout<<"Inorder Traversal of BST:"<<endl;
bst.inorder(root);
cout<<endl;
break;
case 3:
cout<<"Display BST:"<<endl;
bst.display(root,1);
cout<<endl;
break;
case 4:
exit(1);
default:
cout<<"Wrong choice"<<endl;
}
}
}
/* Inserting Element into the Tree */
void BST::insert(node *tree, node *newnode)
{
if (root == NULL)
{
root = new node;
root->info = newnode->info;
root->left = NULL;
root->right = NULL;
cout<<"Root Node is Added"<<endl;
return;
}
if (tree->info == newnode->info)
{
cout<<"Element already in the tree"<<endl;
return;
}
if (tree->info > newnode->info)
{
if (tree->left != NULL)
{
insert(tree->left, newnode);
}
else
{
tree->left = newnode;
(tree->left)->left = NULL;
(tree->left)->right = NULL;
cout<<"Node Added To Left"<<endl;
return;
}
}
else
{
if (tree->right != NULL)
{
insert(tree->right, newnode);
}
else
{
tree->right = newnode;
(tree->right)->left = NULL;
(tree->right)->right = NULL;
cout<<"Node Added To Right"<<endl;
return;
}
}
}
/* In Order Traversal */
void BST::inorder(node *ptr)
{
if (root == NULL)
{
cout<<"Tree is empty"<<endl;
return;
}
if (ptr != NULL)
{
inorder(ptr->left);
cout<<ptr->info<<" ";
inorder(ptr->right);
}
}
/* Display Tree Structure */
void BST::display(node *ptr, int level)
{
int i;
if (ptr != NULL)
{
display(ptr->right, level+1);
cout<<endl;
if (ptr == root)
cout<<"Root->: ";
else
{
for (i = 0;i < level;i++)
cout<<" ";
}
cout<<ptr->info;
display(ptr->left, level+1);
}
}
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