Answer to Question #263357 in C++ for devi

Question

Implement a Stack to store a character in the node. Implement the following operations

push, pop and peek:.

void push (char c);

char pop();

char peek();

int isEmpty();

void printStack();

Answer 1

SOLUTION TO THE ABOVE QUESTION

SOLUTION CODE

// C++ program to Implement a stack
//using singly linked list
#include <iostream>
#include <bits/stdc++.h>
using namespace std;


// Declare linked list node
struct Node
{
	char data;
	struct Node* link;
};


struct Node* top;


//function push to add a character
// data in the stack insert at the beginning
void push(char data)
{
	
	// Create new node temp and allocate memory
	struct Node* temp;
	temp = new Node();


	// Check if stack (heap) is full.
	// Then inserting an element would
	// lead to stack overflow
	if (!temp)
	{
		cout << "\nHeap Overflow";
		exit(1);
	}


	// Initialize data into temp data field
	temp->data = data;


	// Put top pointer reference into temp link
	temp->link = top;


	// Make temp as top of Stack
	top = temp;
}


// function isEmpty to check if  the stack is empty or not


int isEmpty()
{
	return top == NULL;
}


// function to return top element in a stack
char peek()
{
	struct Node* temp;
	
	// Check for stack underflow
	if (top == NULL)
	{
		cout << "\nStack Underflow";
		exit(1);
	}
	else
	{
		temp = top;
		return temp->data;	
	}


}


// function to pop top element from the stack
void pop()
{
	struct Node* temp;
    
	// Check for stack underflow
	if (top == NULL)
	{
		cout << "\nStack Underflow" << endl;
		exit(1);
	}
	else
	{
		
		// Top assign into temp
		temp = top;


		// Assign second node to top
		top = top->link;


		// Destroy connection between
		// first and second
		temp->link = NULL;


		// Release memory of top node
		free(temp);
	}
}


// Function to print all the
// elements of the stack
void printStack()
{
	struct Node* temp;


	// Check for stack underflow
	if (top == NULL)
	{
		cout << "\nStack Underflow";
		exit(1);
	}
	else
	{
		temp = top;
		while (temp != NULL)
		{


			// Print node data
			cout << temp->data << ",  ";


			// Assign temp link to temp
			temp = temp->link;
		}
	}
}


// Driver Code
int main()
{
	
	// Push the elements of stack
	push('a');
	push('b');
	push('c');
	push('d');
	push('e');
	push('f');


	// Display stack elements
	cout<<"\nThe following are the elements of our stack: "<<endl;
	printStack();


	// Print top element of stack
	cout << "\n\nTop element in our stack is "
		<< peek() << endl;


	// Delete top elements of stack
	pop();
	pop();


	// Display stack elements
	cout<<"\nNow the elemnts in our stack after poping are: "<<endl;
	printStack();


	// Print top element of stack
	cout << "\n\nTop element after popping is: "
		<< peek() << endl;
		
	return 0;
}

SAMPLE PROGRAM OUTPUT