HackerRank•Jun 13, 2025

Print the Elements of a Linked List

Hazrat Ali

HackerRank

This exercise focuses on traversing a linked list. You are given a pointer to the  node of a linked list. The task is to print the  of each node, one per line. If the head pointer is , indicating the list is empty, nothing should be printed.

Function Description

Complete the  function with the following parameter(s):

  • a reference to the head of the list

Print

  • For each node, print its  value on a new line (console.log in Javascript).

Input Format

The first line of input contains , the number of elements in the linked list.
The next  lines contain one element each, the  values for each node.

Note: Do not read any input from stdin/console. Complete the printLinkedList function in the editor below.

Constraints

  • where  is the  element of the linked list.

Sample Input

STDIN   Function
-----   --------
2       n = 2
16      first data value = 16
13      second data value = 13

Sample Output

16
13


Solution
#include <bits/stdc++.h>

using namespace std;

class SinglyLinkedListNode {
    public:
        int data;
        SinglyLinkedListNode *next;

        SinglyLinkedListNode(int node_data) {
            this->data = node_data;
            this->next = nullptr;
        }
};

class SinglyLinkedList {
    public:
        SinglyLinkedListNode *head;
        SinglyLinkedListNode *tail;

        SinglyLinkedList() {
            this->head = nullptr;
            this->tail = nullptr;
        }

        void insert_node(int node_data) {
            SinglyLinkedListNode* node = new SinglyLinkedListNode(node_data);

            if (!this->head) {
                this->head = node;
            } else {
                this->tail->next = node;
            }

            this->tail = node;
        }
};


void free_singly_linked_list(SinglyLinkedListNode* node) {
    while (node) {
        SinglyLinkedListNode* temp = node;
        node = node->next;

        free(temp);
    }
}

// Complete the printLinkedList function below.

/*
 * For your reference:
 *
 * SinglyLinkedListNode {
 *     int data;
 *     SinglyLinkedListNode* next;
 * };
 *
 */
void printLinkedList(SinglyLinkedListNode* head) {
    if (!head) return;

    SinglyLinkedListNode* temp = head;

    while (temp != nullptr) {
        cout << temp->data << endl;
        temp = temp->next;
    }
}
int main()
{
    SinglyLinkedList* llist = new SinglyLinkedList();

    int llist_count;
    cin >> llist_count;
    cin.ignore(numeric_limits<streamsize>::max(), '\n');

    for (int i = 0; i < llist_count; i++) {
        int llist_item;
        cin >> llist_item;
        cin.ignore(numeric_limits<streamsize>::max(), '\n');

        llist->insert_node(llist_item);
    }

    printLinkedList(llist->head);

    return 0;
}


















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