/*
 * Simple implementation of unsorted linked list of integers.
 */

#include <stdio.h>

#ifndef LIST_H_
#define LIST_H_ 1

/* Data structure for list node. */
typedef struct int_list_node {
    int data;
    struct int_list_node * next; 
} int_list_node_t;

/* Data structure for list. */
typedef struct int_list {
    int_list_node_t * head;
} int_list_t;

/*
 * Creates list.
 * Returns NULL on error.
 */
int_list_t * int_list_create(void);

/*
 * Free list (and all its elements).
 */
void int_list_free(int_list_t * t);

/* 
 * Insert element into list.
 * Returns -1 on error.
 */
int int_list_insert(int_list_t * l, int elem);

/* 
 * Remove selected element everywhere it occurs.
 * Returns -1 if element is not found.
 */
int int_list_remove(int_list_t * l, int elem);

/*
 * Print all elements of list, one per line.  Parameter "fmt" is 
 * a format string suitable for passing to fprintf.
 */
void int_list_print(FILE * outstream, const char * fmt, int_list_t * l);

#endif /* LIST_H_ */