Product of all leaf nodes of binary tree

Given a binary tree, find the product of all the leaf nodes.

Examples:

Input : 
        1
      /   \
     2     3
    / \   / \
   4   5 6   7
          \
           8
Output :
product = 4 * 5 * 8 * 7 = 1120

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

The idea is to traverse the tree in any fashion and check if the node is the leaf node or not. If the node is the leaf node, multiply node data to a variable prod used to store the products of leaf nodes.

Following is the implementation of above approach.

C++

// CPP program to find product of 
// all leaf nodes of binary tree 
#include <bits/stdc++.h> 
using namespace std; 
  
// struct binary tree node 
struct Node { 
    int data; 
    Node *left, *right; 
}; 
  
// return new node 
Node* newNode(int data) 
{ 
    Node* temp = new Node(); 
    temp->data = data; 
    temp->left = temp->right = NULL; 
    return temp; 
} 
  
// utility function which calculates 
// product of all leaf nodes 
void leafProduct(Node* root, int& prod) 
{ 
    if (!root) 
        return; 
  
    // product root data to prod if 
    // root is a leaf node 
    if (!root->left && !root->right) 
        prod *= root->data; 
  
    // propagate recursively in left 
    // and right subtree 
    leafProduct(root->left, prod); 
    leafProduct(root->right, prod); 
} 
  
// Driver program 
int main() 
{ 
  
    // contruct binary tree 
    Node* root = newNode(1); 
    root->left = newNode(2); 
    root->left->left = newNode(4); 
    root->left->right = newNode(5); 
    root->right = newNode(3); 
    root->right->right = newNode(7); 
    root->right->left = newNode(6); 
    root->right->left->right = newNode(8); 
  
    // variable to store product of leaf nodes 
    int prod = 1; 
    leafProduct(root, prod); 
    cout << prod << endl; 
    return 0; 
} 

Java

// Java program to find product of  
// all leaf nodes of binary tree  
class GFG 
{ 
      
// struct binary tree node  
static class Node  
{  
    int data;  
    Node left, right;  
};  
  
// return new node  
static Node newNode(int data)  
{  
    Node temp = new Node();  
    temp.data = data;  
    temp.left = temp.right = null;  
    return temp;  
}  
  
// product 
static int prod = 1; 
  
// utility function which calculates  
// product of all leaf nodes  
static void leafProduct(Node root )  
{  
    if (root == null)  
        return;  
  
    // product root data to prod if  
    // root is a leaf node  
    if (root.left == null && root.right == null)  
        prod *= root.data;  
  
    // propagate recursively in left  
    // and right subtree  
    leafProduct(root.left);  
    leafProduct(root.right);  
}  
  
// Driver program  
public static void main(String args[]) 
{  
  
    // contruct binary tree  
    Node root = newNode(1);  
    root.left = newNode(2);  
    root.left.left = newNode(4);  
    root.left.right = newNode(5);  
    root.right = newNode(3);  
    root.right.right = newNode(7);  
    root.right.left = newNode(6);  
    root.right.left.right = newNode(8);  
  
    // variable to store product of leaf nodes  
    prod = 1;  
    leafProduct(root);  
    System.out.println(prod ); 
} 
}  
  
// This code is contributed by Arnab Kundu 

C#

// C# program to find product of  
// all leaf nodes of binary tree 
using System; 
  
class GFG 
{ 
      
// struct binary tree node  
public class Node  
{  
    public int data;  
    public Node left, right;  
};  
  
// return new node  
static Node newNode(int data)  
{  
    Node temp = new Node();  
    temp.data = data;  
    temp.left = temp.right = null;  
    return temp;  
}  
  
// product 
static int prod = 1; 
  
// utility function which calculates  
// product of all leaf nodes  
static void leafProduct(Node root )  
{  
    if (root == null)  
        return;  
  
    // product root data to prod if  
    // root is a leaf node  
    if (root.left == null && root.right == null)  
        prod *= root.data;  
  
    // propagate recursively in left  
    // and right subtree  
    leafProduct(root.left);  
    leafProduct(root.right);  
}  
  
// Driver code  
public static void Main(String []args) 
{  
  
    // contruct binary tree  
    Node root = newNode(1);  
    root.left = newNode(2);  
    root.left.left = newNode(4);  
    root.left.right = newNode(5);  
    root.right = newNode(3);  
    root.right.right = newNode(7);  
    root.right.left = newNode(6);  
    root.right.left.right = newNode(8);  
  
    // variable to store product of leaf nodes  
    prod = 1;  
    leafProduct(root);  
    Console.WriteLine(prod ); 
} 
} 
  
// This code has been contributed by 29AjayKumar 