Binary Search Tree: Count number of Leaf nodes

Count number of leaf nodes in Binary Search Tree

#include<stdio.h>

#include<stdlib.h>

struct BST

{

            int data;

            struct BST *lchild;

            struct BST *rchild;

};

typedef struct BST * NODE;

int leaf=0;

NODE get_node()

{

            NODE temp;

            temp = (NODE) malloc(sizeof(struct BST));

            temp->lchild = NULL;

            temp->rchild = NULL;

            return temp;

}

void insert(NODE root, NODE newnode)

{

            if (newnode->data < root->data)

            {

                        if (root->lchild == NULL)

                                    root->lchild = newnode;

                        else

                                    insert(root->lchild, newnode);

            }

            if (newnode->data > root->data)

            {

                        if (root->rchild == NULL)

                                    root->rchild = newnode;

                        else

                                    insert(root->rchild, newnode);

            }

}

int leaf_nodes(NODE root)

{

            if(root == NULL)

                        return 0;

            if(root->lchild == NULL && root->rchild==NULL)

                        leaf++;

            leaf_nodes(root->lchild);

            leaf_nodes(root->rchild);

            return leaf;

}

void main()

{

            int val, i,n, ln;

            NODE root = NULL, newnode;

            printf("\nEnter the number of elements: ");

            scanf("%d",&n);

            for(i=1;i<=n;i++)

            {

                        newnode = get_node();

                        printf("\nEnter The node value: ");

                        scanf("%d", &val);

                        newnode->data = val;

                        if (root == NULL)

                                    root = newnode;

                        else

                                    insert(root, newnode);

            }

            ln = leaf_nodes(root);

            printf("\nTotal number of leaf nodes is: %d", ln);

}

Output:

Enter the number of elements: 12

Enter The node value: 6

Enter The node value: 9

Enter The node value: 5

Enter The node value: 2

Enter The node value: 8

Enter The node value: 15

Enter The node value: 24

Enter The node value: 14

Enter The node value: 7

Enter The node value: 8

Enter The node value: 5

Enter The node value: 2

Total number of leaf nodes is: 4