Question

C++

#include <iostream>

using namespace std;

struct Node {
    int data;
    Node* next;
  
    Node(){
        data = 0;
        next = NULL;
    }
  
    Node(int x){
        data = x;
        next = NULL;
    }
};

struct LinkedList {
    Node* head;
  
    LinkedList(){
        head = NULL;
    }
  
    void append(int value){
      
        if (head == NULL){
            head = new Node(value);
        }
        else{
          
            Node* newNode = new Node(value);
          
            Node* temp = head;
            while(temp->next != NULL){
                temp = temp->next;
            }

            temp->next = newNode;
        }
    }
  
    void insertAt(int index, int value) {
        // Provide your code here
    }
  
    int getValue(int index){
        // Provide your code here
    }
  
    void setValue(int index, int value){
        // Provide your code here
    }
  
    void print (){
        Node* temp = head;
      
        while (temp != NULL) {
            cout << temp->data << endl;
            temp = temp->next;
        }
    }
  
    ~LinkedList(){
        Node* temp = head;
      
        while(temp != NULL){
            temp = temp->next;
            delete head;
            head = temp;
        }
    }
};

int main(int argc, const char * argv[]) {
  
    LinkedList myList;
  
  
    for (int i = 0; i < 6; i++) {
        myList.append(i);
    }
  
    myList.insertAt(2, 77);
  
    myList.insertAt(10, 89);
  
    myList.append(101);
  
    myList.setValue(0, 11);
  
    cout << myList.getValue(2) << endl << endl;
  
    myList.print();
  
    //    Expected output:
    //    77
    //
    //    11
    //    1
    //    77
    //    2
    //    3
    //    4
    //    5
    //    0
    //    0
    //    0
    //    89
    //    101
  
    return 0;
}

The first function you are being asked to implement is int getValueAt(int index) . This function simply returns the value that appears in the array position specified by index .

The second function is void setValueAt(int index, int value) . Its job is to store value in the array position corresponding to index .

The last function to implement is void insertAt(int index, int value) . As the name suggests, it needs to insert the value at the index. It should not overwrite anything. If there is already a something stored at index , it should be shifted to the right. If index is larger than the current size of the list, then it needs to be resized in order to accomodate. If there is a gap between the old size of the list, and the newly inserted value, that gap should be filled with 0s

Answer 1

#include <iostream>

using namespace std;

struct Node {
    int data;
    Node* next;

    Node(){
        data = 0;
        next = NULL;
    }

    Node(int x){
        data = x;
        next = NULL;
    }
};


struct LinkedList {
    Node* head;

    LinkedList(){
        head = NULL;
    }

    void append(int value){

        if (head == NULL){
            head = new Node(value);
        }
        else{

            Node* newNode = new Node(value);

            Node* temp = head;
            while(temp->next != NULL){
                temp = temp->next;
            }


            temp->next = newNode;
        }
    }

    void insertAt(int index, int value) {
    Node *x = new Node;
    x->data = value;
    x->next = NULL;

    if(index == 0) {
        x->next = head;
        head = x;
    } else {
        index--;
        Node *y = head;
        while(y->next && index != 0) {
            y = y ->next;
            index--;
        }   

        if(index == 0) {
            x->next = y->next;
            y->next = x;
        } else {
            // add new nodes.
            while(index != 0) {
                y->next = new Node(0);
                y = y->next;
                index--;
            }
            y->next = new Node(value);

        }

    }
    }

    int getValue(int index){
    Node *y = head;
    while(y && index != 0) {
        y = y ->next;
        index--;
    }   

    if(y == NULL) {
        // invalid index
        return -1;
    } else {
        return y->data;
    }
    }

    void setValue(int index, int value){
    Node *y = head;
    while(y && index != 0) {
        y = y ->next;
        index--;
    }   

    if(y == NULL) {
        // invalid index
        return;
    } else {
        y->data =value;
    }
    }

    void print (){
        Node* temp = head;

        while (temp != NULL) {
            cout << temp->data << endl;
            temp = temp->next;
        }
    }

    ~LinkedList(){
        Node* temp = head;

        while(temp != NULL){
            temp = temp->next;
            delete head;
            head = temp;
        }
    }
};


int main(int argc, const char * argv[]) {

    LinkedList myList;


    for (int i = 0; i < 6; i++) {
        myList.append(i);
    }

    myList.insertAt(2, 77);

    myList.insertAt(10, 89);

    myList.append(101);

    myList.setValue(0, 11);

    cout << myList.getValue(2) << endl << endl;

    myList.print();

    //    Expected output:
    //    77
    //
    //    11
    //    1
    //    77
    //    2
    //    3
    //    4
    //    5
    //    0
    //    0
    //    0
    //    89
    //    101

    return 0;
}

Please upvote, as i have given the exact answer as asked in question. Still in case of any concerns in code, let me know in comments. Thanks!