Question

1.1 llist: Linked list Write a program llist that maintains and manipulates a sorted linked list of integers according to instructions received from standard inpu. The linked list is maintained in order, meaning that each integer will be larger than the one preceeding it. 1list maintains a linked list containing zero or more integers, ordered from least to greatest llist will need to allocate space for new nodes as they are created using malloc; any allocated space should be deallocated using free before 11ist terminates. It supports two operations: insert n Adds an integer n to the list. If n is already present in the list, it does nothing. The instruction format is an i followed by a space and an integer n delete n Removes an integer n from the list. If n is not present in the list, it does nothing. The instruction format is a d followed by a space and an integer n After each command, llist will print the length of the list followed by the contents of the list in order from first (least) to last (greatest) Your program will halt once it reaches the end of standard input Input format Each line of the input contains an instruction. Each line begins with a letter (either "i, or 'd"), followed by a space, and then an integer. A line beginning with-i" indicates that the integer should be inserted into the list. A line beginning with"d" indicates that the integer should be deleted from the list. Your program will not be tested with invalid input. You may choose to have llist terminate in response to invalid input. Output format After performing each instruction, 11ist will print a single line of text containing the length of the list, a colon, and the elements of the list in order, all separated by spaces. Usage Because llist reads from standard input, you may test it by entering inputs line by line from the terminal. You may use any invalid input, such as #, to terminate your session. $./111st

This is being done in c using command line in Linux

Answer 1

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

/* Link list node */
struct Node
{
    int value;
    struct Node* next;
};

/* A utility function to create a new node */
struct Node *newNode(int new_data)
{
    /* allocate node */
    struct Node* new_node = (struct Node*) malloc(sizeof(struct Node));

    /* put in the data  */
    new_node->value  = new_data;
    new_node->next =  NULL;

    return new_node;
}

/* function to insert a new_node in a list. Note that this
  function expects a pointer to head_ref as this can modify the
  head of the input linked list*/
void sortedInsert(struct Node** head_ref, int value)
{
    struct Node* current;

    struct Node* new_node = newNode(value);

    /* Special case for the head end */
    if (*head_ref == NULL || (*head_ref)->value >= new_node->value)
    {
        new_node->next = *head_ref;
        *head_ref = new_node;
    }
    else
    {
        /* Locate the node before the point of insertion */
        current = *head_ref;
        while (current->next!=NULL &&
               current->next->value < new_node->value)
        {
            current = current->next;
        }
        new_node->next = current->next;
        current->next = new_node;
    }
}

/* Function to print linked list */
void printList(struct Node *head)
{
    struct Node *t = head;
    while(t != NULL)
    {
        printf("%d  ", t->value);
        t = t->next;
    }
}

void delete(struct Node *head, int value){
    struct Node * temp = head;
    struct Node * prev = NULL;
    while (temp != NULL){
        // looking for match in list
        if (temp->value == value) {
            // if match is found delete and free the memory
            prev->next = temp->next;
            free(temp);
            break;
        }
        prev = temp;
        temp = temp->next;
    }
}

int main()
{
    /* Start with the empty list */
    struct Node* head = NULL;
    int size = 0, item; // to store the size of list
    char c;
    while (1) {
        scanf("%c", &c); // check which query is inputted by user
        if(c == 'i'){
            //insert into list
            scanf("%d", &item);
            sortedInsert(&head, item);
            size++;
        }

        else if (c == 'd'){
            // delete from list
            scanf("%d", &item);
            delete(head, item);
        }

        else if(c == '#'){
            // if any of the above query is not matched program exists
            break;
        }

        printf("%d : ", size);
        printList(head);
        printf("\n");
        getchar();
    }
}

OUTPUT