Print alternate nodes of a linked list using recursion in C

In this tutorial, we will learn how to print alternate nodes of a linked list using recursion with the help of the C program? By Piyas Mukherjee Last updated : August 02, 2023

Input

A singly linked list whose address of the first node is stored in a pointer, say head

Output

The alternative nodes in the list

Data Structure Used

Singly linked list where each node contains a data element say data, and the address of the immediate next node say next, with Head holding the address of the first node.

Pseudo Code

Function alternate_display(temp):
    Begin
    IF(temp!=NULL){
        Print "temp->data"
        If(temp->next==NULL)
            temp=NULL;
        Else
            alternate_display(temp->next->next);
    }
    Else
        return control to the main function
    End IF-ELSE
End FUNCTION

C program to print alternate nodes of a linked list using recursion

#include <stdio.h>
#include <stdlib.h>

//node structure
typedef struct list {
    int data;
    struct list* next;
} node;

//recursive function
void alternatedisp(node* temp);

int main()
{
    node *head = NULL, *temp, *temp1;
    int choice, count = 0, key;

    //Taking the linked list as input
    do {
        temp = (node*)malloc(sizeof(node));
        if (temp != NULL) {
            printf("\nEnter the element in the list : ");
            scanf("%d", &temp->data);
            temp->next = NULL;
            if (head == NULL) {
                head = temp;
            }
            else {
                temp1 = head;
                while (temp1->next != NULL) {
                    temp1 = temp1->next;
                }
                temp1->next = temp;
            }
        }
        else {
            printf("\nMemory not avilable...node allocation is not possible");
        }
        printf("\nIf you wish to add m ore data on the list enter 1 : ");
        scanf("%d", &choice);
    } while (choice == 1);

    //Now displaying the alternative nodes starting from the begining
    printf("\nDisplaying the alternative items of the list starting from the begining : \n");
    alternatedisp(head);
    printf("NULL\n");

    return 0;
}

//recursive function to display alternative nodes
void alternatedisp(node* temp)
{
    if (temp != NULL) {
        printf("%d->", temp->data);
        if (temp->next == NULL)
            temp = NULL;
        else
            alternatedisp(temp->next->next);
    }
    else
        return;
}

Output

Enter the element in the list : 7

If you wish to add m ore data on the list enter 1 : 1

Enter the element in the list : 6

If you wish to add m ore data on the list enter 1 : 1

Enter the element in the list : 5

If you wish to add m ore data on the list enter 1 : 1

Enter the element in the list : 4 

If you wish to add m ore data on the list enter 1 : 1

Enter the element in the list : 3

If you wish to add m ore data on the list enter 1 : 0

Displaying the alternative items of the list starting from the begining :
7->5->3->NULL