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// Okay to copy/adapt for HW07 in ECE 26400 Spring 2020.
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>
#include "clog.h"

struct Node {
    int value;
    struct Node* next;
}; // Don't forget the SEMICOLON!!!


void append(int value, struct Node** a_head, struct Node** a_tail) {
    struct Node* new_node = malloc(sizeof(*new_node));
    *new_node = (struct Node) { .value=value, .next=NULL };

    if(*a_head == NULL) {
        *a_head = new_node;
        *a_tail = *a_head;
    }
    else {
        (*a_tail) -> next = new_node;
        *a_tail = new_node;
    }
}


void print_list(struct Node* head) {
    for(struct Node* curr = head; curr != NULL; curr = curr -> next) {
        printf("curr -> value == %d\n", curr -> value);
    }
}

/*╒═══════════════════════════════════════════════════════════════════════════════
  │  USE A FOR LOOP (NOT WHILE) TO ITERATE OVER A LINKED LIST, WHERE POSSIBLE.

  │  ____________________________________________________________________
  │  👎 BAD
  │  struct Node* curr = head;
  │  while(curr != NULL) {
  │       ▒▒▒▒▒▒▒▒▒▒
  │       ▒▒▒▒▒▒▒▒▒▒
  │       ▒▒▒▒▒▒▒▒▒▒
  │       ▒▒▒▒▒▒▒▒▒▒
  │       curr = curr -> next;
  │  }

  │  ____________________________________________________________________
  │  👍 GOOD
  │  for(struct Node* curr = head; curr != NULL; curr = curr -> next) {
  │       ▒▒▒▒▒▒▒▒▒▒
  │       ▒▒▒▒▒▒▒▒▒▒
  │       ▒▒▒▒▒▒▒▒▒▒
  │       ▒▒▒▒▒▒▒▒▒▒
  │  }

  ╘════════════════════════════════════════════════════════════════════════════════*/


int main(int argc, char* argv[]) {
    // Empty list
    struct Node* head = NULL; // This is it.  This is an empty list.
    struct Node* tail = head;
    log_addr(head);
    log_addr(tail);

    append(5, &head, &tail);

    log_msg("After adding one node (.value=5)\n");
    log_addr(head);
    log_addr(tail);
    log_int(head -> value);
    log_int(tail -> value);
    
    append(6, &head, &tail);
    log_msg("After adding a second node (.value=6)\n");
    log_addr(head);
    log_addr(tail);
    log_int(head -> value);
    log_int(tail -> value);
    
    append(7, &head, &tail);
    log_msg("After adding a third node (.value=7)\n");
    log_addr(head);
    log_addr(tail);
    log_int(head -> value);
    log_int(tail -> value);
    
    print_list(head);
    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */

© Copyright 2020 Alexander J. Quinn         This content is protected and may not be shared, uploaded, or distributed.