Please explain each line of codes. It's queue lab in C

* This program implements a queue supporting both FIFO and LIFO 

 * operations. 

 * 

 * It uses a singly-linked list to represent the set of queue elements 

 */ 

#include  

#include  

#include  

#include "harness.h" 

#include "queue.h" 

/* 

 Create empty queue. 

 Return NULL if could not allocate space. 

*/ 

 1. queue_t *q_new() 

 2. 3. { 4. queue_t *q = malloc(sizeof(queue_t)); 5. /* What if malloc returned NULL? */ 

 6. if (q == NULL) 

 7. return q; 8. q->head = NULL; 9. q->tail = NULL; 10. q->n = 0; 11. return q; 12. }