1. Single Linked List

#include <iostream>

#define MAX_NODE 10002

using namespace std;

typedef class c_node
{
public :
	int				data;
	class c_node	*nxt;

	class c_node	*get_new_node(int new_data)
	{
		data = new_data;
		nxt = nullptr;
		return (this);
	}
}					t_node;

t_node	g_mem_pool[MAX_NODE];
t_node	*g_head;
int		g_node_cnt;

void	print_lst(void);

void	init_lst(void)
{
	g_node_cnt = 0;
	g_head = g_mem_pool[g_node_cnt++].get_new_node(-1); // dummy
}

void	lst_add_front(int data)
{
	t_node	*new_node;

	new_node = g_mem_pool[g_node_cnt++].get_new_node(data);
	new_node->nxt = g_head->nxt;
	g_head->nxt = new_node;
}

void	lst_add_back(int data)
{
	t_node	*cur;
	t_node	*new_node;

	cur = g_head;
	while (cur->nxt)
		cur = cur->nxt;
	new_node = g_mem_pool[g_node_cnt++].get_new_node(data);
	cur->nxt = new_node;
}

void	lst_add_by_idx(int data, int idx)
{
	t_node	*cur;
	t_node	*new_node;

	cur = g_head;
	while (--idx && cur->nxt)
		cur = cur->nxt;
	new_node = g_mem_pool[g_node_cnt++].get_new_node(data);
	new_node->nxt = cur->nxt;
	cur->nxt = new_node;
}

void	lst_rm_by_data(int data)
{
	t_node	*cur, *trail;

	trail = cur = g_head;
	while (cur)
	{
		if (cur->data == data)
		{
			trail->nxt = cur->nxt;
			return ;
		}
		trail = cur;
		cur = cur->nxt;
	}
}

int	get_lst(int output[MAX_NODE])
{
	t_node	*cur;
	int		cnt;

	cur = g_head->nxt;
	cnt = 0;
	while (cur)
	{
		output[cnt] = cur->data;
		++cnt;
		cur = cur->nxt;
	}
	return (cnt);
}

void	print_lst(void)
{
	t_node	*cur;

	cur = g_head->nxt;
	cout << "lst: ";
	while (cur->nxt)
	{
		cout << cur->data << " ";
		cur = cur->nxt;
	}
	cout << endl;
}

2. Double Linked List

#include <iostream>

#define MAX_NODE 10002

using namespace std;

typedef class c_node
{
public :
	int				data;
	class c_node	*prv;
	class c_node	*nxt;

	class c_node	*get_new_node(int new_data)
	{
		data = new_data;
		prv = nxt = nullptr;
		return (this);
	}
}					t_node;

t_node	g_mem_pool[MAX_NODE];
t_node	*g_head;
t_node	*g_tail;
int		g_node_cnt;

void	print_lst(void);

void	init_lst(void)
{
	g_node_cnt = 0;
	g_head = g_mem_pool[g_node_cnt++].get_new_node(-1);
	g_tail = g_mem_pool[g_node_cnt++].get_new_node(-1);
	g_head->nxt = g_tail;
	g_tail->prv = g_head;
}

void	lst_add_front(int data)
{
	t_node	*new_node;

	new_node = g_mem_pool[g_node_cnt++].get_new_node(data);
	new_node->prv = g_head;
	new_node->nxt = g_head->nxt;
	g_head->nxt->prv = new_node;
	g_head->nxt = new_node;
}

void	lst_add_back(int data)
{
	t_node	*new_node;

	new_node = g_mem_pool[g_node_cnt++].get_new_node(data);
	new_node->prv = g_tail->prv;
	new_node->nxt = g_tail;
	g_tail->prv->nxt = new_node;
	g_tail->prv = new_node;
}

void	lst_add_by_idx(int data, int idx)
{
	t_node	*cur;
	t_node	*new_node;

	cur = g_head;
	while (--idx && cur->nxt)
		cur = cur->nxt;
	new_node = g_mem_pool[g_node_cnt++].get_new_node(data);
	new_node->prv = cur;
	new_node->nxt = cur->nxt;
	cur->nxt->prv = new_node;
	cur->nxt = new_node;
}

int	get_node_idx(int data)
{
	t_node	*cur;
	int		cnt;

	cur = g_head->nxt;
	cnt = 1;
	while (cur)
	{
		if (cur->data == data)
			return (cnt);
		++cnt;
		cur = cur->nxt;
	}
	return (-1);
}

void	lst_rm_by_data(int data)
{
	t_node	*cur, *trail;

	cur = g_head;
	while (cur)
	{
		if (cur->data == data)
		{
			trail->nxt = cur->nxt;
			cur->nxt->prv = trail;
			return ;
		}
		trail = cur;
		cur = cur->nxt;
	}
}

int	get_lst(int output[MAX_NODE])
{
	t_node	*cur;
	int		cnt;

	cur = g_head->nxt;
	cnt = 0;
	while (cur->nxt)
	{
		output[cnt] = cur->data;
		++cnt;
		cur = cur->nxt;
	}
	return (cnt);
}

int	get_reversed_lst(int output[MAX_NODE])
{
	t_node	*cur;
	int		cnt;

	cur = g_tail->prv;
	cnt = 0;
	while (cur->prv)
	{
		output[cnt] = cur->data;
		++cnt;
		cur = cur->prv;
	}
	return (cnt);
}

void	print_lst(void)
{
	t_node	*cur;

	cur = g_head->nxt;
	cout << "lst: ";
	while (cur->nxt)
	{
		cout << cur->data << " ";
		cur = cur->nxt;
	}
	cout << endl;
}