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@nihal-singh
Created September 20, 2018 13:32
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/* Deleting a node from Binary search tree */
#include<iostream>
using namespace std;
struct Node {
int data;
struct Node *left;
struct Node *right;
};
//Function to find minimum in a tree.
Node* FindMin(Node* root)
{
while(root->left != NULL) root = root->left;
return root;
}
// Function to search a delete a value from tree.
struct Node* Delete(struct Node *root, int data) {
if(root == NULL) return root;
else if(data < root->data) root->left = Delete(root->left,data);
else if (data > root->data) root->right = Delete(root->right,data);
// Wohoo... I found you, Get ready to be deleted
else {
// Case 1: No child
if(root->left == NULL && root->right == NULL) {
delete root;
root = NULL;
}
//Case 2: One child
else if(root->left == NULL) {
struct Node *temp = root;
root = root->right;
delete temp;
}
else if(root->right == NULL) {
struct Node *temp = root;
root = root->left;
delete temp;
}
// case 3: 2 children
else {
struct Node *temp = FindMin(root->right);
root->data = temp->data;
root->right = Delete(root->right,temp->data);
}
}
return root;
}
//Function to visit nodes in Inorder
void Inorder(Node *root) {
if(root == NULL) return;
Inorder(root->left); //Visit left subtree
printf("%d ",root->data); //Print data
Inorder(root->right); // Visit right subtree
}
// Function to Insert Node in a Binary Search Tree
Node* Insert(Node *root,char data) {
if(root == NULL) {
root = new Node();
root->data = data;
root->left = root->right = NULL;
}
else if(data <= root->data)
root->left = Insert(root->left,data);
else
root->right = Insert(root->right,data);
return root;
}
int main() {
/*Code To Test the logic
Creating an example tree
5
/ \
3 10
/ \ \
1 4 11
*/
Node* root = NULL;
root = Insert(root,5); root = Insert(root,10);
root = Insert(root,3); root = Insert(root,4);
root = Insert(root,1); root = Insert(root,11);
// Deleting node with value 5, change this value to test other cases
root = Delete(root,5);
//Print Nodes in Inorder
cout<<"Inorder: ";
Inorder(root);
cout<<"\n";
}
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