No_of_leaf_nodes.cpp

#include <bits/stdc++.h>
using namespace std;

///--------------------Structure of Node---------------------------//

struct Node         
{
    int value;      
    struct Node *left, *right;      
    struct Node *root;
    
};

///------------End of structure------------//

///------------To create a node and assign data to each section of node------------//

struct Node *create ( int val )
{
    struct Node *p = new Node;      //New Node
    p->value = val;                 //
    p->left = p->right = NULL;
    p->root = NULL;
    return p;
}

///-----------------------------------------------------------------------------------------//

///-------------------To create and assign nodes in the binary according values--------------//

struct Node* tree(Node* t, int v){
	 if (t == NULL)
        return create(v);

    if (v < t->value)
        t->left = tree(t->left, v);
    else
        t->right = tree(t->right, v);

    return t;
}

///------------------------------------------------------------------------------------------//

///------------Number of leaf nodes in the binary tree------------//
int leaf_count( struct Node* p )  
{  
    if ( p == NULL )      
        return 0;  
    if ( p->left == NULL && p->right == NULL )  
        return 1;         
    else
        return leaf_count( p->left ) + leaf_count( p->right );  
} 

///---------------------------------------------------------------//

///-------------------Driver function----------------------------//

int main()
{
	int size;
	Node *root = new Node;      
	root = NULL;

	cout<<"Enter the size of array : ";
	cin>>size;          //size of array

    int a[size];        //'a' is an array to store values
    
	cout<<"Enter the elements in array : ";
	for(int i=0;i<size;i++)
    {
        cin>>a[i];      //Taking inputs
    }
    
	for(int i = 0; i < size; i++)
	{
	    root = tree(root, a[i]);        //calling tree function to assign nodes in tree according to values 
	}
    
    cout << "\n No. of leaf nodes in tree: "<<leaf_count( root ) << endl;       //printing no. of leaf nodes
    
    return 0;
}

///------------------End of driver function----------------------//