0x19. C - Stacks, Queues - LIFO, FIFO

Learning Objectives

At the end of this project, you are expected to be able to explain to anyone, without the help of Google:

General

What do LIFO and FIFO mean What is a stack, and when to use it What is a queue, and when to use it What are the common implementations of stacks and queues What are the most common use cases of stacks and queues What is the proper way to use global variables

Data structures

Please use the following data structures for this project. Don’t forget to include them in your header file.

/**
 * struct stack_s - doubly linked list representation of a stack (or queue)
 * @n: integer
 * @prev: points to the previous element of the stack (or queue)
 * @next: points to the next element of the stack (or queue)
 *
 * Description: doubly linked list node structure
 * for stack, queues, LIFO, FIFO
 */
typedef struct stack_s
{
        int n;
        struct stack_s *prev;
        struct stack_s *next;
} stack_t;

/**
 * struct instruction_s - opcode and its function
 * @opcode: the opcode
 * @f: function to handle the opcode
 *
 * Description: opcode and its function
 * for stack, queues, LIFO, FIFO
 */
typedef struct instruction_s
{
        char *opcode;
        void (*f)(stack_t **stack, unsigned int line_number);
} instruction_t;

Compilation & Output

• Your code will be compiled this way:

$ gcc -Wall -Werror -Wextra -pedantic -std=c89 *.c -o monty

• Any output must be printed on stdout
• Any error message must be printed on stderr
• Here is a link to a GitHub repository that could help you making sure your errors are printed on stderr