How To Calculate Diameter of Binary Tree?

				
					#include <stdio.h>  
#include <stdlib.h>
// For Using C++ Language, we can use the Namespace Std;

struct node // Structure For Binary Tree Node
{ 
    int data; // Int Val or Data To Get The Current Node Or New Node Values
    struct node *left, *right; // Pointer For Left And Right Subtree
};

struct node* newNode(int data); // Recursion Stack Space For New Node Root
int height(struct node* node); // Declaration Of Function Height

int max(int a, int b) // Function To Calculate Maximum Depth Or Maximum Value
{ 
    return (a > b) ? a : b; // When Maximum Diameter Found, Return It
}

int diameter(struct node* tree) // Finding Binary Tree Int Diameter Path
{
    if (tree == NULL) // If Treenode Root Is Null, It Will Return Int 0
    {
        return 0;
    }
    int val; // Ans Variable

    int lh = height(tree->left); // Then Height Function Used For Left Subtree
    int rh = height(tree->right); // Then Height Function Used For Right Subtree

    // We Will Use The Same Recursive Function For Both Left And Right Subtree
    int ld = diameter(tree->left); 
    int rd = diameter(tree->right);

    return max(lh + rh + 1, max(ld, rd)); // Return The Current Diameter Of The Tree 
}

int height(struct node* node) // Function To Get Height Of The Current Subtree
{
    if (node == NULL) // If Treenode Root Is Null, Then Return The Null Data
    {
        return 0;
    }

    // If Treenode Root Is Not Null, Then Return The Path Length
    return 1 + max(height(node->left), height(node->right)); // Find Maximum Height
}

struct node* newNode(int data) // Function To Add Number Of Nodes In A Tree
{
    // First, Create The Binary Tree Node Root And Provide Values There
    struct node* node = (struct node*)malloc(sizeof(struct node));
    node->data = data; 
    node->left = NULL; // Create A New Node In The Root Left
    node->right = NULL; // Create A New Node In The Root Right

    return (node); 
}

int main() 
{
    // Given A Binary Tree Using Input Data Call Stack
    struct node* root = newNode(10); // Current Node Root
    // Giving Values To Two Nodes, Left And Right Children
    root->left = newNode(8);
    root->right = newNode(30);
    // Giving More Input Int Values To Create Left And Right Subtrees
    root->left->left = newNode(5);
    root->right->right = newNode(40);
    int val;

    // When Maximum Diameter Found, We Have To Print It To Current Node
    printf("The Diameter Of Binary Tree: %d",diameter(root));
    return 0;
}