#include<stdio.h>
#include<string.h>
# define max 6

struct data_type
{
	
	char name[30];
	char topic[200];
	int rollno;
};
	struct stack_type
	{
	struct data_type data[max];
	int top;
	};
	void initialize(struct stack_type*);
	void push(struct data_type, struct stack_type*);
	struct data_type pop(struct stack_type*);
	void disno(struct stack_type);
	void disall(struct stack_type);

main()
{
	struct stack_type stack;
	struct data_type tempdata;
	int opt;
	initialize (&stack);
	clrscr();
	do
	{
	printf("\n\n\t\*+-*+-*+-*+-*+-*+-*+-*+-*+-*+-*+-*+-*+-*+-\n");
	printf("\t\t\t\t*****Menu*****\n\n");
	printf("\t\t 1.Add a Topic\n");
	printf("\t\t 2.Remove a Topic\n");
	printf("\t\t 3.Display Topics Based On Roll Number\n");
	printf("\t\t 4.Display All The Topics \n");
	printf("\t\t 5.Sort By Roll Number\n");
	printf("\t\t 6.Exit\n\n");
	printf("\t\t\t Enter your choice:");
	scanf("%d",&opt);
	printf("\n\t\t*+-*+-*+-*+-*+-*+-*+-*+-*+-*+-*+-*+-*+-*+-*+\n");
	switch(opt)
	{
		case 1:
		if (stack.top==max-1)
		{
		printf("\n\n\t\t\t Stack is FULL\n");
		getche();
		}
		else
		{
		clrscr();
		printf("\n\n\n\t\t Enter The roll Number: ");
		scanf("%d",&tempdata.rollno);
		printf("\n\t\t Enter The Name: ");
		scanf("%s",tempdata.name);
		printf("\n\t\t Enter The topic: ");
		scanf("%s",tempdata.topic);
		push (tempdata,&stack);
		}
		clrscr();
		break;

		case 2:
		if(stack.top==-1)
		{
		printf("\n\n\t\t\t Stack is EMPTY \n");
		getche();
		}
		else
		{
		clrscr();
		tempdata=pop(&stack);
		printf("\n\t\t The Removed Element Is: \n");
		printf("\t\t roll Number:%d\t\n",tempdata.rollno);
		printf("\t\t Name:%s\t\n",tempdata.name);
		printf("\t\t topic:%s\t\n",tempdata.topic);
		getche();
		}
		break;

		case 3:
			clrscr();
			disno(stack);
			break;

		case 4:
			clrscr();
			disall(stack);
			break;
		case 5: clrscr();
			disno(stack);
			break;

		case 6:
			clrscr();
			printf("\n\n\n\n\n\n\n\n\n\n\t\t\t PROGRAM IS OVER \n");
			break;

		default:
			printf("\n\t\t ERROR.. The number you enterd is not avaliable\n");
			getche();
			}
		}
		while (opt!=6);
		getche();
		}


		/* function starts here */

		void initialize (struct stack_type*pstack)
		{
			pstack -> top=-1;
		}

		 void push (struct data_type element, struct stack_type *pstack)
		{
			pstack -> top=pstack ->top+1;
			pstack -> data[pstack ->top]=element;
		}


		 struct data_type pop (struct stack_type *pstack)
		{
		struct data_type temp;
		temp=pstack->data [pstack->top];
		pstack ->top=pstack->top-1;
		return (temp);
		}

		void disno (struct stack_type stack)
		 {
		 int i,a=0;
		 int rollno;
		 struct data_type temp;
		 printf("\n\t\t\t Enter the roll Number:");
		 scanf("%d",&rollno);
		 for (i=stack.top;i>=0;i--)
		{
			temp=stack.data[i];
			if(rollno==temp.rollno)
			{
				fflush(stdout);
				printf("\n\t\t\t The Name is =%s\n",temp.name);
				fflush(stdout);
				printf("\n\t\t\t The topic is =%s\n",temp.topic);
				a=1;
			}
		 }
			 if (a!=1)
				printf("\n\t\t\t The number you have entered is not available\n");
		 }

		  void disall (struct stack_type stack)
		  {
		  int i;
		  struct data_type temp;
		  if(stack.top==-1)
			printf("\n\t\t\t NO RECORD ENTERED \n");
		  else
			{
			printf("\t\t%s\t%s\t%s","roll No\t", "Name\t", "topic\n");
			for (i=stack.top; i>=0; i--)
			{
				temp = stack.data[i];
				fflush(stdout);
				printf("\t\t%d\t\t" ,temp.rollno);
				fflush(stdout);
				printf("%s\t\t",temp.name);
				fflush(stdout);
				printf("%s\t\n",temp.topic);
			}
			}

		  }