Contoh Program Double Linked List Circular dan Cara Memahaminya

Double Linked List Circular

Pengertian secara umumnya DLLC itu Linked list yang menggunakan pointer, dimana setiap node memiliki 3 field, yaitu:

• 1 field pointer yang menunjuk pointer berikutnya “next“,
• 1 field menunjuk pointer sebelumnya ” prev “,
• 1 field yang berisi data untuk node tersebut .

Double Linked List Circular pointer next dan prev nya menunjuk kedirinya sendiri secara circular. Bentuk Node DLLC

Ilustrasi Double Linked List Circular

Setiap node pada linked list mempunyai field yang berisi data dan pointer ke node berikutnya & ke node sebelumnya.  Untuk pembentukan node baru , mulanya pointer next dan prev akan menunjuk ke nilai NULL. Selanjutnya pointer prev akan menunjuk ke node sebelumnya , dan pointer next akan menunjuk ke node selanjutnya pada list.

Contoh program Double Linked List Circular :

#include <conio.h>
#include <stdio.h>
struct TNode{
char data[30];
TNode *next;
TNode *prev;
};
TNode *head, *tail;
void init(void);
int isEmpty(void);
void insertDepan(char databaru[30]);
void insertBelakang (char databaru[30]);
void inserttengah(char databaru[30], int pilihdepan, int pilihbelakang);
void tampil(void);
void hapusDepan(void);
void hapusBelakang(void);
void deletetengah(int pilih);
void clear(void);
int cari(char elemen[30]);
main()
{
////////////////////////////////
char pilih;
char elm[30];
int depan,belakang;
init();
do
{
printf("\n");
printf("\t\t===================================\n");
printf("\t\t||       CONTOH PROGRAM        ||\n");
printf("\t\t||  DOUBLE LINK LIST CIRCULAR  ||\n");
printf("\t\t===================================\n");
printf("          \t\tMENU PILIHAN :           \n");
printf("\t\t===================================\n");
printf("\t\t[1] MASUKKAN DATA DARI DEPAN\n");
printf("\t\t[2] MASUKKAN DATA DARI BELAKANG\n");
printf("\t\t[3] MASUKKAN DATA DI TENGAH\n");
printf("\t\t[4] TAMPILKAN DATA\n");
printf("\t\t[5] HAPUS DATA PALING DEPAN\n");
printf("\t\t[6] HAPUS DATA PALING BELAKANG\n");
printf("\t\t[7] HAPUS DATA DI TENGAH\n");
printf("\t\t[8] HAPUS SEMUA DATA\n");
printf("\t\t[9] CARI DATA\n");
printf("\t\t[0] KELUAR\n");
printf("\t\t===================================\n\n");
printf("\t\t===================================\n\n");
printf("\n");
printf("\t\t->->PILIHAN ANDA   :  ");
scanf("%s",&pilih);
switch(pilih)
{
case '1':clrscr();
tampil();
printf("\n");
printf("   \t\tMASUKKAN DATA DARI DEPAN\n");
printf("\t\t----------------------------\n");
printf("\t\t:: MASUKKAN DATA : ");
scanf("%s",&elm);
insertDepan(elm);
getch();
clrscr();
break;
case '2':clrscr();
tampil();
printf("\n");
printf("   \t\tMASUKKAN DATA BELAKANG\n");
printf("\t\t----------------------------\n");
printf("\t\t:: MASUKKAN DATA : ");
scanf("%s",&elm);
insertBelakang(elm);
clrscr();
break;
case '3':clrscr();
tampil();
printf("\n");
printf("   \t\tMASUKKAN DATA DARI TENGAH\n");
printf("\t\t----------------------------\n");
printf("\t\t:: MASUKKAN DATA : ");
scanf("%s",&elm);
printf("\t\t:: DATA DEPAN : ");
scanf("%i",&depan);
printf("\t\t:: DATA BELAKANG : ");
scanf("%i",&belakang);
inserttengah(elm,depan,belakang);
getch();
clrscr();
break;
case '4':clrscr();
tampil();
printf("\t\t-------------\n\n");
printf("\t\tPress Enter to Continue..");
getch();
clrscr();
break;
case '5':clrscr();
tampil();
hapusDepan();
printf("\n");
printf("\t\t-------------\n");
printf("\t\tPress Enter to Continue..");
getch();
clrscr();
break;
case '6':clrscr();
tampil();
hapusBelakang();
printf("\n");
printf("\t\t-------------\n");
printf("\t\tPress Enter to Continue..");
getch();
clrscr();
break;
case '7':clrscr();
tampil();
printf("\n");
printf("   \t\tMENGHAPUS DATA DARI TENGAH\n");
printf("\t\t----------------------------\n");
printf("\t\t:: DATA NO : ");
scanf("%i",&depan);
deletetengah(depan);
getch();
clrscr();
break;
case '8':clrscr();
clear();
printf("\t\tDATA TELAH DIHAPUS SEMUA\n");
printf("\t\t-------------\n");
printf("\t\tPress Enter to Continue..");
getch();
clrscr();
break;
case '9':clrscr();
printf("\n");
printf("  \t\t MASUKKAN DATA YANG DICARI\n");
printf("\t\t----------------------------\n");
printf("\t\t:: MASUKKAN DATA : ");
scanf("%s",&elm);
if(cari(elm)==1){
printf("\n\t\tdata  success ditemukan");
}else{
printf("\n\t\tMaaf data tidak ditemukan");
}
getch();
clrscr();
break;
case '0': break;
getch();
clrscr();
default:printf("\t\tSalah pilih...\n");
break;
}
}while(pilih!='0');
}
/////////////////////////////////
void init(void){
head = NULL;
tail = NULL;
}
/////////////////////////////////
int isEmpty(void){
if(tail == NULL) return 1;
else return 0;
}
//////////////////////////////////
void insertDepan(char databaru[30]){
TNode *baru;
int i;
baru = new TNode;
for(i=0;i<=30;i++){
baru->data[i] = databaru[i];
}
baru->next = baru;
baru->prev = baru;
if(isEmpty()==1){
head=baru;
tail=baru;
head->next = head;
head->prev = head;
tail->next = tail;
tail->prev = tail;
}
else {
baru->next = head;
head->prev = baru;
head = baru;
head->prev = tail;
tail->next = head;
}
printf("\n\t\t\Data masuk\n");
printf("\t\tPress Enter to Continue..");
}
////////////////////////////////////////////////////
void insertBelakang (char databaru[30]){
TNode *baru,*bantu;
int i;
baru = new TNode;
for(i=0;i<=30;i++){
baru->data[i] = databaru[i];
}
baru->next = baru;
baru->prev = baru;
if(isEmpty()==1){
head=baru;
tail=baru;
head->next = head;
head->prev = head;
tail->next = tail;
tail->prev = tail;
}
else {
tail->next = baru;
baru->prev = tail;
tail = baru;
tail->next = head;
head->prev = tail;
}
printf("\t\tData masuk\n");
printf("\t\tPress Enter to Continue..");
}
//////////////////////////////////////////////
void tampil(void){
int i=0;
if(isEmpty()==0){
do{
i++;
printf("\t\t%i. %s\n",i,head->data);
printf("\t\t===================\n");
head=head->next;
}while(head!=tail->next);
printf("\n");
} else printf("\t\t\t..Masih kosong..\n\n");
}
//////////////////////////////////////////////
void hapusDepan(void){
TNode *hapus;
char d[30];
int i;
if (isEmpty()==0){
if(head != tail){
hapus = head;
for (i=0;i<=30;i++){
d[i] = hapus->data[i];
}
head = head->next;
tail->next = head;
head->prev = tail;
delete hapus;
} else {
for (i=0;i<=30;i++){
d[i] = head->data[i];
}
head = NULL;
tail = NULL;
}
printf("\t\t%s terhapus\n",d);
} else printf("\t\tMasih kosong\n");
}
//////////////////////////////////////////
void hapusBelakang(void){
TNode *hapus;
char d[30];
int i;
if (isEmpty()==0){
if(head != tail){
hapus = tail;
for (i=0;i<=30;i++){
d[i] = hapus->data[i];
}
tail = tail->prev;
tail->next = head;
head->prev = tail;
delete hapus;
} else {
for (i=0;i<=30;i++){
d[i] = head->data[i];
}
head = NULL;
tail = NULL;
}
printf("\t\t%s terhapus\n",d);
} else printf("\t\tMasih kosong\n");
}
//////////////////////////////////////////
void clear(void){
TNode *bantu,*hapus;
if (isEmpty()==0){
bantu = head;
while(bantu->next!=head){
hapus = bantu;
bantu = bantu->next;
delete hapus;
}
head = NULL;
}
}
//////////////////////////////////////////
//////////////////////////////////////
int cari(char elemen[30]){
int i=0;
int status=0;
if(isEmpty()==0){
do{
i++;
if(head->data[i]==elemen[i]){
status=1;
}else head=head->next;
}while(head!=tail->next && i<=30);
return(status);
} else printf("\t\tMasih kosong\n");
}
/////////////////////////////////////
void inserttengah(char databaru[30], int pilihdepan, int pilihbelakang){
TNode *baru,*bantu,*depan,*belakang;
char elemen[30];
int i;
int j;
baru = new TNode;
for(i=0;i<=30;i++){
baru->data[i] = databaru[i];
}
baru->next = baru;
baru->prev = baru;
if(isEmpty()==1){
head=baru;
tail=baru;
head->next = head;
head->prev = head;
tail->next = tail;
tail->prev = tail;
}else{
depan = head;
belakang = head;
for(i=1;i<pilihdepan;i++){
depan=depan->next;
}
for(i=1;i<pilihbelakang;i++){
belakang=belakang->next;
}
depan->next = baru;
baru->prev = depan;
baru->next = belakang;
belakang->prev = baru;
}
printf("\t\tData masuk\n");
printf("\t\tPress Enter to Continue..");
}
////////////////////////////////////////////////////////
void deletetengah(int pilih){
TNode *hapusdepan,*hapusbelakang,*hapustengah;
char d[30];
int i,j;
if (isEmpty()==0){
if(head != tail){
hapusdepan = head;
hapusbelakang = head;
hapustengah = head;
for(i=1;i<pilih;i++){
hapusdepan=hapusdepan->next;
}
for(i=1;i<(pilih+2);i++){
hapusbelakang=hapusbelakang->next;
}
for(i=1;i<=pilih;i++){
hapustengah=hapustengah->next;
}
for(j=1;j<pilih;j++){
for (i=0;i<=30;i++){
d[i] = hapustengah->data[i];
}
hapustengah = hapustengah->next;
}
delete hapustengah;
hapusdepan->next = hapusbelakang;
hapusbelakang->prev=hapusdepan;
} else {
for (i=0;i<=30;i++){
d[i] = hapustengah->data[i];
}
head = NULL;
tail = NULL;
}
printf("\t\t%s Success terhapus\n",d);
} else printf("\t\tMasih kosong\n");
}