Find Number of Occurrences of All Elements in a Linked List

#include

#include

#include

struct node

    int num;

    struct node *next;

};

struct node_occur

    int num;

    int times;

    struct node_occur *next;

};

void create(struct node **);

void occur(struct node *, struct node_occur **);

void release(struct node **);

void release_2(struct node_occur **);

void display(struct node *);

void disp_occur(struct node_occur *);

int main()

    struct node *p = NULL;

    struct node_occur *head = NULL;

    int n;

    printf("Enter data into the list\n");

    create(&p);

    printf("Displaying the occurence of each node in the list:\n");

    display(p);

    occur(p, &head);

    disp_occur(head);

    release(&p);

    release_2(&head);

     return 0;

 void occur(struct node *head, struct node_occur **result)

    struct node *p;

    struct node_occur *temp, *prev;

    p = head;

    while (p != NULL)

        temp = *result;

        while (temp != NULL && temp->num != p->num)

            prev = temp;

            temp = temp->next;

        if (temp == NULL)

            temp = (struct node_occur *)malloc(sizeof(struct node_occur));

            temp->num = p->num;

            temp->times = 1;

            temp->next = NULL;

            if (*result != NULL)

                prev->next = temp;

            else

                *result = temp;

        else

            temp->times += 1;

        p = p->next;

void create(struct node **head)

    int c, ch;

    struct node *temp, *rear;

do

        printf("Enter number: ");

        scanf("%d", &c);

        temp = (struct node *)malloc(sizeof(struct node));

        temp->num = c;

        temp->next = NULL;

        if (*head == NULL)

            *head = temp;

        else

            rear->next = temp;

        rear = temp;

        printf("Do you wish to continue [1/0]: ");

        scanf("%d", &ch);

    } while (ch != 0);

    printf("\n");

void display(struct node *p)

    while (p != NULL)

        printf("%d\t", p->num);

        p = p->next;

    printf("\n");

 void disp_occur(struct node_occur *p)

    printf("***************************\n  Number\tOccurence\n***************************\n");

    while (p != NULL)

        printf("    %d\t\t%d\n", p->num, p->times);

        p = p->next;

 void release(struct node **head)

    struct node *temp = *head;

    *head = (*head)->next;

    while ((*head) != NULL)

        free(temp);

        temp = *head;

        (*head) = (*head)->next;

void release_2(struct node_occur **head)

    struct node_occur *temp = *head;

    *head = (*head)->next;

    while ((*head) != NULL)

        free(temp);

        temp = *head;

        (*head) = (*head)->next;

Output

            Enter data into the list

Enter number: 1

Do you wish to continue [1/0]: 1

Enter number: 2

Do you wish to continue [1/0]: 1

Enter number: 3

Do you wish to continue [1/0]: 1

Enter number: 2

Do you wish to continue [1/0]: 1

Enter number: 4

Do you wish to continue [1/0]: 1

Enter number: 2

Do you wish to continue [1/0]: 1

Enter number: 6

Do you wish to continue [1/0]: 1

Enter number: 1

Do you wish to continue [1/0]: 0

Displaying the occurence of each node in the list:

1          2          3          2          4          2          6          1

***************************

  Number         Occurence

***************************

    1                  2

    2                  3

    3                  1

    4                  1

    6                  1

Find the first Common Element between the 2 given Linked Lists

#include

#include

#include

struct node

    int num;

    struct node *next;

};

void create(struct node **);

int find(struct node *, struct node *);

void release(struct node **);

void display(struct node *);

int main()

    struct node *p = NULL, *q = NULL;

    int result;

    printf("Enter data into the list\n");

    create(&p);

    printf("Enter data into the list\n");

    create(&q);

    printf("Displaying list1:\n");

    display(p);

    printf("Displaying list2:\n");

    display(q);

    result = find(p, q);

    if (result)

        printf("The first matched element is %d.\n", result);

    else

        printf("No matching element found.\n");

    release (&p);

    return 0;

int find(struct node *p, struct node *q)

    struct node *temp;

    while (p != NULL)

        temp = q;

        while (temp != NULL)

            if (temp->num == p->num)

                return p->num;

            temp = temp->next;

        p = p->next;

     return 0;

void create(struct node **head)

    int c, ch;

    struct node *temp, *rear;

do

        printf("Enter number: ");

        scanf("%d", &c);

        temp = (struct node *)malloc(sizeof(struct node));

        temp->num = c;

        temp->next = NULL;

        if (*head == NULL)

            *head = temp;

        else

            rear->next = temp;

        rear = temp;

        printf("Do you wish to continue [1/0]: ");

        scanf("%d", &ch);

    } while (ch != 0);

    printf("\n");

void display(struct node *head)

    while (head != NULL)

        printf("%d\t", head->num);

        head = head->next;

    printf("\n");

void release(struct node **head)

    struct node *temp;

    while ((*head) != NULL)

        temp = *head;

        (*head) = (*head)->next;

        free(temp);

Output

Enter data into the list1

Enter number: 2

Do you wish to continue [1/0]: 1

Enter number: 8

Do you wish to continue [1/0]: 1

Enter number: 5

Do you wish to continue [1/0]: 1

Enter number: 6

Do you wish to continue [1/0]: 0

Enter data into the list2

Enter number: 3

Do you wish to continue [1/0]: 1

Enter number: 5

Do you wish to continue [1/0]: 1

Enter number: 9

Do you wish to continue [1/0]: 0

Displaying list1:

2          8          5          6

Displaying list2:

3          5          9

The first matched element is 5.