Answers for "linked list in c++ stl"

linkedlist implementation in c++

#include <iostream>

using namespace std;

struct node
{
    int data;
    node *next;
};

class linked_list
{
private:
    node *head,*tail;
public:
    linked_list()
    {
        head = NULL;
        tail = NULL;
    }

    void add_node(int n)
    {
        node *tmp = new node;
        tmp->data = n;
        tmp->next = NULL;

        if(head == NULL)
        {
            head = tmp;
            tail = tmp;
        }
        else
        {
            tail->next = tmp;
            tail = tail->next;
        }
    }
};

int main()
{
    linked_list a;
    a.add_node(1);
    a.add_node(2);
    return 0;
}

linked list in c++ stl

#include <bits/stdc++.h>
#include <iostream>
#include <list>
#include <iterator>

#define ll long long

using namespace std;

//function to print all the elements of the linked list
void showList(list <int> l){
	list <int> :: iterator it; //create an iterator according to the data structure
	for(it = l.begin(); it != l.end(); it++){
		cout<<*it<<" ";
	}
	
}	


int main(){
	
	list <int> l1;
	list <int> l2;
	
	for(int i=0; i<10; i++){
		l1.push_back(i*2); //fill list 1 with multiples of 2
		l2.push_back(i*3); //fill list 2 with multiples of 3
	}
	
	cout<<"content of list 1 is "<<endl;
	showList(l1);
	cout<<endl;
	
	cout<<"content of list 2 is "<<endl;
	showList(l2);
	cout<<endl;
	
	//reverse the first list
	l1.reverse();
	showList(l1);
	cout<<endl;
	
	//sort the first list
	l1.sort();
	showList(l1);
	cout<<endl;
	
	//removing an element from both sides
	l2.pop_front();
	l2.pop_back();
	
	//adding an element from both sides
	l2.push_back(10);
	l2.push_front(20);
	
	
    return 0;
}

cpp linked list

struct Node {
  int data;
  struct Node *next;
};

C++ linked list

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */

void trimLeftTrailingSpaces(string &input) {
    input.erase(input.begin(), find_if(input.begin(), input.end(), [](int ch) {
        return !isspace(ch);
    }));
}

void trimRightTrailingSpaces(string &input) {
    input.erase(find_if(input.rbegin(), input.rend(), [](int ch) {
        return !isspace(ch);
    }).base(), input.end());
}

vector<int> stringToIntegerVector(string input) {
    vector<int> output;
    trimLeftTrailingSpaces(input);
    trimRightTrailingSpaces(input);
    input = input.substr(1, input.length() - 2);
    stringstream ss;
    ss.str(input);
    string item;
    char delim = ',';
    while (getline(ss, item, delim)) {
        output.push_back(stoi(item));
    }
    return output;
}

ListNode* stringToListNode(string input) {
    // Generate list from the input
    vector<int> list = stringToIntegerVector(input);

    // Now convert that list into linked list
    ListNode* dummyRoot = new ListNode(0);
    ListNode* ptr = dummyRoot;
    for(int item : list) {
        ptr->next = new ListNode(item);
        ptr = ptr->next;
    }
    ptr = dummyRoot->next;
    delete dummyRoot;
    return ptr;
}

void prettyPrintLinkedList(ListNode* node) {
  while (node && node->next) {
      cout << node->val << "->";
      node = node->next;
  }

  if (node) {
    cout << node->val << endl;
  } else {
    cout << "Empty LinkedList" << endl;
  }
}

int main() {
    string line;
    while (getline(cin, line)) {
        ListNode* head = stringToListNode(line);
        prettyPrintLinkedList(head);
    }
    return 0;
}

linked list class c++ basic implementation

template<typename T>
class list {
  public:

    struct node {
        T value;
        node* next;
    };

    list() : hd(nullptr), tl(nullptr) {}

    node* head() { return hd; }
    node* tail() { return tl; }

    void insert(node* prior, T value);

    node* at(int i);    

    void erase(node* prior);
    void clear();

    void push_back(T value);
    void pop_back();

    void push_front(T value);
    void pop_front();

    int size();    

  private:
    node* hd, tl;
}