Contoh Program Double Linked List

Selain kita mempelajari Single linked list dalam struktur data, kita juga mempelajari double linked list yang operasinya sama dengan single linked list.
langsung saja ini contoh Codingnya :

#include<stdio.h>
#include<stdlib.h>

typedef struct simpul node;
struct simpul
{
int data;
node *prev;
node *next;
};

node *head = NULL, *tail = NULL, *baru;

void allocate_node (int x)
{
baru = (node *) malloc (sizeof(node));
if(baru==NULL)
{
printf("Alokasi Gagal\n");
exit(1);
}
else
{
baru->data=x;
baru->next=NULL;
baru->prev=NULL;
}
}

//head = tail = baru;


void buat_list()
{
printf("Data Masih Kosong, List akan dibuat dengan data tersebut\n");
system("PAUSE");
head = tail = baru;
}

void sisip_awal()
{
if(head==NULL && tail==NULL)
buat_list();
else
{
baru->next=head;
head->prev=baru;
head=baru;
}
}

void sisip_akhir()
{
if(head==NULL && tail==NULL)
buat_list();
else
{
baru->prev=tail;
tail->next=baru;
tail=baru;
}

}

void sisip_sebelum(int s)
{
node *before=head;
int cek=0;
if(before->next==NULL)
cek=1;
else
{
while(before->next->data!=s)
{
before=before->next;
if(before->next==NULL)
{
cek = 1;
break;
}
}
}
if(cek==0)
{
baru->prev = before;
baru->next = before->next;
before->next->prev = baru;
before->next = baru;
}
else
void gatot();
}

void sisip_sesudah(int s)
{
node *after=tail;
int cek=0;
if(after->prev == NULL)
cek=1;
else
{
while(after->prev->data!=s)
{
after=after->prev;
if(after->prev==NULL)
{
cek = 1;
break;
}
}
}
if(cek==0)
{
baru->next = after;
baru->prev = after->next;
after->prev->next = baru;
after->prev = baru;
}
else
void gatot();
}

void free_node(node *p)
{
free(p);
printf("DATA TERHAPUS\n");
}

void hapus_satu()
{
node *hapus = head;
head = NULL;
tail = NULL;
free_node(hapus);
}

void hapus_awal()
{
node *hapus = head;
head->next->prev = NULL;
head =  head->next;
free_node(hapus);
}

void hapus_akhir()
{
node *hapus = tail;
tail->prev->next = NULL;
tail =  tail->prev;
free_node(hapus);
}

void hapus_tengah(int s)
{
node *hapus=head;
int cek=0;
while(hapus->data!=s)
{
if(hapus->next==NULL)
{
cek=1;
break;
}
hapus = hapus->next;
}
if(cek==0)
{
hapus->prev->next = hapus->next;
hapus->next->prev = hapus->prev;
free_node(hapus);
}
else
void gadel();
}

void gatot()
{
printf("SIMPUL BARU TIDAK DAPAT DISISIPKAN\n");
//system("PAUSE");
}

void gadel()
{
printf("TIDAK ADA DATA YANG DIHAPUS\n");
//system("PAUSE");
}

void tampil()
{
node *p= head;
printf("\nData Simpul ==>  ");
while(p!=NULL)
{
printf("%d ", p->data);
p=p->next;
}
printf("\n\n");
}

void main()
{
head=baru;
int pilih, data, s;
char lagi='y';
while(lagi=='y')
{
system("CLS");
void awal();
tampil();
printf("Menu Pilihan : \n");
printf("1. Sisip Awal\n");
printf("2. Sisip Akhir\n");
printf("3. Sisip Sebelum Simpul\n");
printf("4. Sisip Sesudah Simpul\n");
printf("5. Hapus Awal\n");
printf("6. Hapus Akhir\n");
printf("7. Hapus Tengah\n");
printf("\nPilih No            : ");
scanf("%d", &pilih);
switch(pilih)
{
case 1 :
printf("Masukkan data       : ");
scanf("%d", &data);
allocate_node(data);
sisip_awal();
break;
case 2 :
printf("Masukkan data       : ");
scanf("%d", &data);
allocate_node(data);
sisip_akhir();
break;
case 3 :
printf("Masukkan data       : ");
scanf("%d", &data);
allocate_node(data);
if(head==NULL && tail==NULL)
buat_list();
else
{
printf("Dimasukkan sebelum  : ");
scanf("%d",&s);
if(s==head->data)
sisip_awal();
else
sisip_sebelum(s);
}
break;
case 4 :
printf("Masukkan data       : ");
scanf("%d", &data);
allocate_node(data);
if(head==NULL && tail==NULL)
buat_list();
else
{
printf("Dimasukkan sesudah  : ");
scanf("%d",&s);
if(s==tail->data)
sisip_akhir();
else
sisip_sesudah(s);
}
break;
case 5 :
if(head == NULL && tail == NULL)
gadel();
else if(head == tail)
hapus_satu();
else
hapus_awal();
break;
case 6 :
if(head == NULL && tail == NULL)
gadel();
else if(head == tail)
hapus_satu();
else
hapus_akhir();
break;
case 7 :
printf("Data yang dihapus   : ");
scanf("%d", &data);
if(head == NULL && tail == NULL)
gadel();
else if(data == head->data && data == tail->data && head == tail)
hapus_satu();
else if(data == head->data)
hapus_awal();
else if(data == tail->data)
hapus_akhir();
else
hapus_tengah(data);
break;
}
fflush(stdin);
printf("Lagi (y/t) ? ");
scanf("%c", &lagi);
}
}

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