Contoh Program Stack Menggunakan Single Linked List

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

typedef int ItemType;
typedef struct simpul node;
struct simpul
{
 ItemType item;
 node *next;
};

struct Stack{
 node *TOS;
};

node *baru;

void awal()
{
 puts("===================================================");
 puts("=         PROGRAM STACK DENGAN LINKED LIST        =");
 puts("===================================================\n");
 puts("NRP   :  7411030828");
 puts("Nama  :  M.Faishal Imam Choiri\n");
}

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

void inisialisasi(Stack *s)
{
 s->TOS = NULL;
}

int kosong(Stack *s)
{
 return s->TOS==NULL;
}

void push(Stack *s)
{
 baru->next = s->TOS;
 s->TOS = baru;
}

ItemType pop(Stack *s)
{
 node *temp;
 if(kosong(s))
 {
  printf("Data Kosong\n");
  return ' ';
 }
 else
 {
  temp = s->TOS;
  s->TOS = s->TOS->next;
  return temp->item;
  free(temp);
  temp=NULL;
 }
}

void tampil(Stack *s)
{
 Stack bantu;
 bantu = *s;
 printf("\nData Simpul ==>  ");
 while(bantu.TOS!=NULL)
 {
  printf("%d ", bantu.TOS->item);
  bantu.TOS = bantu.TOS->next;
 }
 printf("\n\n");
}

void main()
{
 int pilih, data;
 char lagi='y';
 Stack ujung;

 inisialisasi(&ujung);
 while(lagi=='y')
 {
  system("CLS");
  awal();
  //tampil(&ujung);
  printf("Menu Pilihan : \n");
  printf("1. Push\n");
  printf("2. Pop\n");
  printf("3. Tampilkan Stack\n");
  printf("\nPilih No          : ");
  scanf("%d", &pilih);
  switch(pilih)
  {
  case 1:
   printf("Masukkan data     : ");
   scanf("%d", &data);
   allocate_node(data);
   push(&ujung);
   break;
  case 2:
   pop(&ujung);
   break;
  case 3:
   tampil(&ujung);
   break;
  }
  fflush(stdin);
  printf("Lagi (y/t) ? ");
  scanf("%c", &lagi);
 }
}