C Program to Count Number of Non Leaf Nodes of a given Tree

This C Program counts the number of non leaf nodes of a given tree.

Here is source code of the C Program to count the number of non leaf nodes of a given tree. The C program is successfully compiled and run on a Linux system. The program output is also shown below.

```
/* 
```

 * C Program to Count Number of Non Leaf Nodes of a given Tree

```
 */
```
```
#include <stdio.h>
```
```
#include <stdlib.h>
```
```
 
```
```
struct btnode
```
```
{
```
```
    int value;
```
```
    struct btnode *r,*l;
```
```
} *root = NULL, *temp = NULL;
```
```
 
```
```
void create();
```
```
void insert();
```
```
void add(struct btnode *t);
```
```
void inorder(struct btnode *t);
```
```
 
```
```
int count = 0;
```
```
 
```
```
void main()
```
```
{
```
```
    int ch;
```
```
 
```
```
    printf("\nOPERATIONS ---");
```
```
    printf("\n1] Insert ");
```
```
    printf("\n2] Display");
```
```
    printf("\n3] Exit ");    
```
```
 
```
```
    while (1)
```
```
    {                        
```

        printf("\nEnter your choice : ");

```
        scanf("%d", &ch);
```
```
        switch (ch)
```
```
        {
```
```
        case 1:    
```
```
            insert();
```
```
            break;
```
```
        case 2: 
```
```
            inorder(root);
```

            printf("\nNumber of non leaf nodes: %d", count);

```
            break;
```
```
        case 3: 
```
```
            exit(0);
```
```
        default :     
```

            printf("Wrong choice, Please enter correct choice  ");

```
            break;    
```
```
        }
```
```
    }
```
```
}
```
```
 
```

/* To create a new node with the data from the user */

```
void create()
```
```
{
```
```
    int data;
```
```
 
```

    printf("Enter the data of node : ");

```
    scanf("%d", &data);
```

    temp = (struct btnode* ) malloc(1*(sizeof(struct btnode)));

```
    temp->value = data;
```
```
    temp->l = temp->r = NULL;
```
```
}
```
```
 
```

/* To check for root node and then create it */

```
void insert()
```
```
{
```
```
    create();
```
```
 
```
```
    if (root == NULL)
```
```
        root = temp;
```
```
    else
```
```
        add(root);
```
```
}
```
```
 
```

/* Search for the appropriate position to insert the new node */

```
void add(struct btnode *t)
```
```
{
```

    if ((temp->value > t->value) && (t->r != NULL))        /* value more than root node value insert at right */

```
        add(t->r);
```

    else if ((temp->value > t->value) && (t->r == NULL))

```
        t->r = temp;
```

    else if ((temp->value < t->value) && (t->l != NULL))        /* value less than root node value insert at left */

```
        add(t->l);
```

    else if ((temp->value < t->value) && (t->l == NULL))

```
        t->l = temp;
```
```
}
```
```
 
```

/* To display and count the sum of non leaf nodes */

```
void inorder(struct btnode *t)
```
```
{
```
```
    if (t->l != NULL)
```
```
        inorder(t->l);
```

    if ((t->l != NULL) ||  (t->r != NULL))

```
    {
```

        count++;                            /* To count number of non leaf nodes */

```
        printf("%d ->",t->value);
```
```
    }
```
```
    if (t->r != NULL)
```
```
        inorder(t->r);
```
```
}
```

$ cc tree31.c
$ a.out
 OPERATIONS ---
1] Insert 
2] Display
3] Exit 
Enter your choice : 1
Enter the data of node : 40
 
Enter your choice : 1
Enter the data of node : 20
 
Enter your choice : 1
Enter the data of node : 60
 
Enter your choice : 1
Enter the data of node : 10
 
Enter your choice : 1
Enter the data of node : 30
 
Enter your choice : 1
Enter the data of node : 80
 
Enter your choice : 1
Enter the data of node : 90
 
Enter your choice : 2
20->40->60->80->
Number of non leaf nodes: 4
Enter your choice : 3
 
                40
                /\
               /  \
             20    60
             / \    \
           10  30   80
                     \
                     90

Sanfoundry Global Education & Learning Series – 1000 C Programs.

Here’s the list of Best Reference Books in C Programming, Data-Structures and Algorithms

If you wish to look at programming examples on all topics, go to C Programming Examples.

« Prev Page - C Program to Copy File into Another File

» Next Page - C Program to find Next higher Value of N with same 1’s

Deep Dive @ Sanfoundry: