Delete duplicate nodes from sorted linked list in c

C program for Delete duplicate nodes from sorted linked list. Here problem description and explanation.

/*
    C program for
    Delete duplicate nodes in sorted linked list
*/
#include <stdio.h>
#include <stdlib.h>

// Linked List LinkNode
struct LinkNode
{
    int data;
    struct LinkNode *next;
};
// Singly linked list 
struct SingleLL
{
    struct LinkNode *head;
    struct LinkNode *tail;
};
// Returns the new linked list
struct SingleLL *newLinkedList()
{
    // Create memory of head and tail Nodes
    struct SingleLL *sll = (struct SingleLL *)
    malloc(sizeof(struct SingleLL));
    if (sll == NULL)
    {
        printf("Memory overflow\n");
    }
    else
    {
        sll->head = NULL;
        sll->tail = NULL;
    }
    return sll;
}
// Handles the request of adding new node at end of linked list
void addNode(struct SingleLL *sll, int data)
{
    // Create dynamic node
    struct LinkNode *node = (struct LinkNode *)
    malloc(sizeof(struct LinkNode));
    if (node == NULL)
    {
        printf("Memory overflow to Create LinkNode\n");
        return;
    }
    else
    {
        // Set initial node value
        node->data = data;
        node->next = NULL;
    }
    if (sll->head == NULL)
    {
        sll->head = node;
    }
    else
    {
        sll->tail->next = node;
    }
    sll->tail = node;
}
// Display linked list element
void display(struct LinkNode *node)
{
    if (node == NULL)
    {
        return;
    }
    struct LinkNode *temp = node;
    // iterating linked list elements
    while (temp != NULL)
    {
        printf(" %d →", temp->data);
        // Visit to next node
        temp = temp->next;
    }
    printf(" NULL\n");
}
// Remove the duplicate nodes from sorted singly linked list
void deleteDuplicate(struct SingleLL *sll)
{
    if (sll->head == NULL)
    {
        return;
    }
    else
    {
        // Auxiliary variables
        struct LinkNode *temp = sll->head->next;
        struct LinkNode *current = sll->head;
        struct LinkNode *hold = NULL;
        // Find and remove duplicate
        while (temp != NULL)
        {
            // Check duplicate node 
            if (current->data == temp->data)
            {
                //  When node key are same
                hold = temp;
            }
            else
            {
                // When node key are not same
                current = temp;
            }
            // Visit to next node
            temp = temp->next;
            if (hold != NULL)
            {
                // Modified link value
                current->next = temp;
                // Remove nodes
                free(hold);
                hold = NULL;
            }
            else
            {
                sll->tail = current;
            }
        }
    }
}
int main(int argc, char
    const *argv[])
{
    struct SingleLL *sll = newLinkedList();
    // Sorted Linked list node
    addNode(sll, 1);
    addNode(sll, 1);
    addNode(sll, 2);
    addNode(sll, 3);
    addNode(sll, 4);
    addNode(sll, 4);
    addNode(sll, 4);
    addNode(sll, 5);
    addNode(sll, 6);
    addNode(sll, 7);
    printf(" Before Delete \n");
    display(sll->head);
    deleteDuplicate(sll);
    printf(" After Delete \n");
    display(sll->head);
    return 0;
}

Output

 Before Delete
 1 → 1 → 2 → 3 → 4 → 4 → 4 → 5 → 6 → 7 → NULL
 After Delete
 1 → 2 → 3 → 4 → 5 → 6 → 7 → NULL


Please share your knowledge to improve code and content standard. Also submit your doubts, and test case. We improve by your feedback. We will try to resolve your query as soon as possible.

New Comment







© 2021, kalkicode.com, All rights reserved