Write a program to implement stack data structure using linked list.
A stack is a container of objects that are inserted and removed according to the last-in first-out (LIFO) principle. In other words the item which in inserted(pushed) last, will be the first item to be popped.
Operations to be performed.
1] Push if stack is not full
2] Pop if stack is not empty
3] Top of stack
#include<stdio.h>
#include<stdlib.h>
#define MAX 5
unsigned int inc = 0;
typedef struct SingleLinkList
{
int num;
struct SingleLinkList *next;
}SLL;
void push(int,SLL**);
int pop(SLL**);
int top_of_stack(SLL*);
int print(SLL*);
int main()
{
SLL *hp = 0;
int n,op;
printf("1] Push 2] Pop 3] Top of stack 4] Print 0] Exit\n");
scanf("%d",&op);
while(op != 0)
{
switch(op)
{
case 1:
if(inc == 5)
{
printf("Stack is full\n");
break;
}
printf("Enter Value to Push = ");
scanf("%d",&n);
push(n,&hp);
printf("Count = %d\n",print(hp));
break;
case 2:
if(inc == 0)
{
printf("Stack Empty\n");
break;
}
printf("Popped Value is = %d\n",pop(&hp));
printf("Count = %d\n",print(hp));
break;
case 3:
printf("Top of stack = %d\n",top_of_stack(hp));
break;
case 4:
printf("Count = %d\n",print(hp));
break;
default:
printf("Invalid option.\n");
}
printf("1] Push 2] Pop 3] Top of stack 4] Print 0] Exit\n");
scanf("%d",&op);
}
return 0;
}
void push(int n,SLL**p)
{
SLL *p1;
p1 = (SLL*)malloc(sizeof(SLL));
p1->num = n;
inc++;
p1->next = *p;
*p = p1;
}
int pop(SLL**p)
{
SLL *p1;
int n;
p1 = *p;
n = p1->num;
*p = p1->next;
free(p1);
inc--;
return n;
}
int top_of_stack(SLL*p)
{
return (p->num);
}
int print(SLL*p)
{
unsigned int c = 0;
while(p)
{
c++;
printf("%d ",p->num);
p = p->next;
}
printf("\n");
return c;
}
Output
1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 1 Enter Value to Push = 10 10 Count = 1 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 1 Enter Value to Push = 20 20 10 Count = 2 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 1 Enter Value to Push = 30 30 20 10 Count = 3 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 1 Enter Value to Push = 40 40 30 20 10 Count = 4 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 1 Enter Value to Push = 50 50 40 30 20 10 Count = 5 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 1 Stack is full 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 1 Stack is full 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 2 Popped Value is = 50 40 30 20 10 Count = 4 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 2 Popped Value is = 40 30 20 10 Count = 3 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 3 Top of stack = 30 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 2 Popped Value is = 30 20 10 Count = 2 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 4 20 10 Count = 2 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 2 Popped Value is = 20 10 Count = 1 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 2 Popped Value is = 10 Count = 0 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 2 Stack Empty 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 2 Stack Empty 1] Push 2] Pop 3] Top of stack 4] Print 0] Exit 0