addLast
Lesson 6 of 14 in Coddy's Doubly Linked List - Data Structures Series #6 course.
Challenge
EasyAdd a method addLast to the DoublyLinkedList class.
It gets an integer value and inserts a new node carrying that value at the end of the list. Make sure to wire both directions of the link (prev on the new node, next on the old tail), and update head if the list was empty.
Try it yourself
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "doublylinkedlist.h"
int main() {
DoublyLinkedList ll;
DoublyLinkedList_init(&ll);
char line[256];
while (fgets(line, sizeof(line), stdin)) {
line[strcspn(line, "\r\n")] = '\0';
char* cmd = strtok(line, " \t");
if (!cmd) continue;
if (strcmp(cmd, "state") == 0) printf("%s %s %d\n", ll.head == NULL ? "true" : "false", ll.tail == NULL ? "true" : "false", ll.count);
if (strcmp(cmd, "count") == 0) printf("%d\n", ll.count);
if (strcmp(cmd, "headValue") == 0) printf("%d\n", Node_getValue(ll.head));
if (strcmp(cmd, "tailValue") == 0) printf("%d\n", Node_getValue(ll.tail));
if (strcmp(cmd, "addFirst") == 0) {
char* arg = strtok(NULL, " \t");
DoublyLinkedList_addFirst(&ll, atoi(arg));
}
if (strcmp(cmd, "addLast") == 0) {
char* arg = strtok(NULL, " \t");
DoublyLinkedList_addLast(&ll, atoi(arg));
}
}
return 0;
}
