linked list implementation in c++

linked list in c++ using class:

This is singly linked list implementation, it travel in one direction that is forward direction so it is also called as “Forward list”.

insertion and deletion in linked list in c++ program:

Below program explain insertion, deletion, display and other functionalities.

source code of linked list in c++

/*
Program: Singly Linklist 
Author: Alpha Master
Date: 20 Oct 2021
*/

//Header File
#include<iostream>

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

class linklist
{
	node* ptr;
	public:
		linklist();
		~linklist();
		void append(int num);
		void display();
		void addAtBeg(int num);
		bool find(int num);
		void remove(int num);
};

linklist::linklist()
{
	ptr = nullptr;
}

linklist::~linklist()
{
	node* tmp = nullptr;
	while(ptr != nullptr)
	{
		tmp = ptr->next;
		delete ptr;
		ptr = tmp;
	
	}
}

void linklist:: display()
{
	node* tmp = ptr;
	while(tmp != nullptr)
	{
		std::cout<<tmp->data<<" ";
		tmp = tmp->next;
	}
	std::cout<<std::endl;
}

void linklist::append(int num)
{
	//first element
	if(ptr == nullptr)
	{
		ptr = new node;
		ptr->data = num;
		ptr->next = nullptr;
	}
	else
	{
		//traverse till end
		node* tmp = ptr;
		node* pre = nullptr;
		while(tmp != nullptr)
		{
			pre = tmp;
			tmp = tmp->next;
		}
		pre->next = new node;
		pre->next->data = num;
		pre->next->next = nullptr;
	}
}
void linklist::addAtBeg(int num)
{
	node* tmp = nullptr;
	tmp = ptr;
	ptr = new node;
	ptr->data = num;
	ptr->next = tmp;
}

bool linklist::find(int num)
{
	node* tmp = ptr;
	bool result = false;
	while(tmp != nullptr)
	{
		if(tmp->data == num)
		{
			result = true;
			break;
		}
		tmp = tmp->next;
	}
	return result;
}

void linklist::remove(int num)
{
	node* tmp = ptr;
	node* pre = tmp;
	while(tmp != nullptr)
	{
		if(tmp->data == num)
		{
			if(tmp == ptr)
				ptr = ptr->next;
			else
				pre->next = tmp->next;
			//delete
			delete tmp;
			break;	
		}
		pre = tmp;
		tmp = tmp->next;	
	}
}

int main()
{
	std::cout<<"Single LinkList"<<std::endl;
	linklist obj;	
	obj.append(1);
	obj.append(2);
	obj.append(3);
	obj.addAtBeg(4);
	obj.append(5);
	obj.display();
	std::cout<<obj.find(3)<<std::endl;
	std::cout<<obj.find(5)<<std::endl;
	std::cout<<"Remove 4"<<std::endl;
	obj.remove(4);
	obj.display();
	std::cout<<"Remove 2"<<std::endl;
	obj.remove(2);
        obj.display();
	std::cout<<"Remove 5"<<std::endl;
        obj.remove(5);
	obj.display();

	return 0;
}

Output:

Single LinkList
4 1 2 3 5 
1
1
Remove 4
1 2 3 5 
Remove 2
1 3 5 
Remove 5
1 3