Computer Tutorial

#include <stdio.h> #include <string.h> #include <stdlib.h> #include <stdbool.h> struct node { int data; int key; struct node *next; struct node *prev; }; //this link always point to first Link struct node *head = NULL; //this link always point to last Link struct node *last = NULL; struct node *current = NULL; //is list empty bool isEmpty(){ return head == NULL; } int length(){ int length = 0; struct node *current; for(current = head; current != NULL; current = current->next){ length++; } return length; } //display the list in from first to last void displayForward(){ //start from the beginning struct node *ptr = head; //navigate till the end of the list printf("\n[ "); while(ptr != NULL){ printf("(%d,%d) ",ptr->key,ptr->data); ptr = ptr->next; } printf(" ]"); } //display the list from last to first void displayBackward(){ //start from the last struct node *ptr = last; //navigate till the start of the list printf(&quo

#include <stdio.h> #include <string.h> #include <stdlib.h> #include <stdbool.h> struct node { int data; int key; struct node *next; }; struct node *head = NULL; struct node *current = NULL; //display the list void printList() { struct node *ptr = head; printf("\n[ "); //start from the beginning while(ptr != NULL) { printf("(%d,%d) ",ptr->key,ptr->data); ptr = ptr->next; } printf(" ]"); } //insert link at the first location void insertFirst(int key, int data) { //create a link struct node *link = (struct node*) malloc(sizeof(struct node)); link->key = key; link->data = data; //point it to old first node link->next = head; //point first to new first node head = link; } //delete first item struct node* deleteFirst() { //save reference to first link struct node *tempLink = head; //mark next to first link as first head = head->next; //return the deleted link return tempLink; } //is list empty bool isEmpty() { retur