write a programme of stack using linked list.

#include<stdio.h>

#include<stdlib.h>

void display(void);

void push(void);

void pop(void);

struct link_list

{

int data;

struct link_list *next;

}*start=NULL;

typedef struct link_list node;

node *current,*nnew;

int main()

{

int a;

char ch;

do

{

printf("\n enter your choice\n1->push\n2->pop\n3->display\n");

scanf("%d",&a);

switch(a)

{

case 3:

display();

break;

case 2:

       pop();

       break;

case 1:

push();

break;

default:

printf("wrong choice");

}

printf("\n press any key to continue and press n to quit->");

scanf("%s",&ch);

}while(ch!='n');

return (0);

}

void push(void)

{

int i=0,k;

printf("how many elements you want to enter->");

scanf("%d",&i);

while(i!=0)

{

nnew=malloc(sizeof(node));

nnew->next=NULL;

if(start==NULL)

{

printf("enter any integer data->");

scanf("%d",&k);

nnew->data=k;

start=nnew;

current=start;

printf("\t%d pushed successfully\n",start->data);

}

else

{

printf("enter any integer data->");

scanf("%d",&k);

nnew->data=k;

nnew->next=start;

start=nnew;

printf("\t%d pushed successfully\n",start->data);

}

i--;

}

}

void display(void)

{

              current=start;

              printf("\n");

              while(current!=NULL)

              {

              printf("\t%d\n" ,current->data);

              current=current->next;

       }

}

void pop(void)

{

       int count=0;

       printf("how many elements you want to pop->");

       scanf("%d",&count);

       current=start;

       while(count!=0)

       {

       if(start==NULL)

              printf("stack underflow!");

              else

              {

       printf("%d popped successfully\n",start->data);

       current=start;

start=start->next;

free(current);

}

       count--;

}

}