Add files via upload

Author: lezirean

SQ4.class

@@ -0,0 +1,89 @@
+import static java.lang.System.exit;
+
+class StackUsingLinkedlist {
+
+	private class Node {
+		int data; 
+		Node link; 
+		Node prev;
+	}
+	
+	Node top;
+
+	StackUsingLinkedlist(){
+		this.top = null;
+	}
+
+	public void push(int x) {
+		Node temp = new Node();
+
+		if (temp == null) {
+			System.out.print("\nHeap Overflow");
+			return;
+		}
+
+		temp.data = x;
+		temp.prev = temp.link;
+		temp.link = top;
+		top = temp;
+	}
+
+	public boolean isEmpty(){
+		return top == null;
+	}
+
+	public int peek(){
+		if (!isEmpty()) {
+			return top.data;
+		}
+		else {
+			System.out.println("Stack is empty");
+			return -1;
+		}
+	}
+
+	public void pop() {
+		if (top == null) {
+			System.out.print("\nStack Underflow");
+			return;
+		}
+
+		top = (top).link;
+	}
+
+	public void display(){
+		if (top == null) {
+			System.out.printf("\nStack Underflow");
+			exit(1);
+		}
+		else {
+			Node temp = top;
+			while (temp != null) {
+				System.out.printf("%d->", temp.data);
+				temp = temp.link;
+			}
+		}
+	}
+}
+
+public class SQ4 {
+	public static void main(String[] args){
+		StackUsingLinkedlist obj = new StackUsingLinkedlist();
+
+		obj.push(11);
+		obj.push(22);
+		obj.push(33);
+		obj.push(44);
+
+		obj.display();
+
+		System.out.print("\nTop element is " + obj.peek() + "\n");
+
+		obj.pop();
+		obj.pop();
+
+		obj.display();
+
+		System.out.print("\nTop element is " + obj.peek() + "\n");
+	}
+}

SQ4.java

@@ -0,0 +1,75 @@
+class QNode {
+	char key;
+	QNode next;
+
+	public QNode(char key){
+		this.key = key;
+		this.next = null;
+	}
+}
+
+class Queue {
+	QNode front, rear;
+
+	public Queue(){
+		this.front = this.rear = null;
+	}
+
+	void enqueue(char key){
+		QNode temp = new QNode(key);
+
+		if (this.rear == null){
+			this.front = this.rear = temp;
+			return;
+		}
+
+		this.rear.next = temp;
+		this.rear = temp;
+	}
+
+	char dequeue(){
+		if (this.front == null)
+			return '0';
+
+		QNode temp = this.front;
+		this.front = this.front.next;
+
+
+		if (this.front == null)
+			this.rear = null;
+
+		return temp.key;
+	}
+}
+
+
+public class SQ5 {
+	public static void main(String[] args){
+		Queue q = new Queue();
+		q.enqueue('E');
+		q.enqueue('A');
+		q.enqueue('S');
+		System.out.println(q.dequeue());
+		q.enqueue('Y');
+		System.out.println(q.dequeue());
+		q.enqueue('Q');
+		q.enqueue('U');
+		q.enqueue('E');
+		System.out.println(q.dequeue());
+		System.out.println(q.dequeue());
+		System.out.println(q.dequeue());
+		q.enqueue('S');
+		q.enqueue('T');
+		System.out.println(q.dequeue());
+		System.out.println(q.dequeue());
+		System.out.println(q.dequeue());
+		q.enqueue('I');
+		q.enqueue('O');
+		System.out.println(q.dequeue());
+		q.enqueue('N');
+		System.out.println(q.dequeue());
+		System.out.println(q.dequeue());
+		System.out.println(q.dequeue());
+	}
+}
+

SQ5.class

@@ -0,0 +1,150 @@
+import java.util.*;
+
+class SQ6{
+	static class Node{
+		char data;
+		Node prev, next;
+
+		static Node getnode(char data){
+		Node newNode = new Node();
+		newNode.data = data;
+		newNode.prev = newNode.next = null;
+		return newNode;
+		}
+	}
+
+	static class Deque {
+		Node front;
+		Node rear;
+		int Size;
+
+		Deque(){
+			front = rear = null;
+			Size = 0;
+		}
+
+		boolean isEmpty() { return (front == null); }
+
+		int size() { return Size; }
+
+		void insertFront(char data){
+			Node newNode = Node.getnode(data);
+
+			if (newNode == null)
+				System.out.print("OverFlow\n");
+			else {
+				if (front == null)
+					rear = front = newNode;
+				else {
+					newNode.next = front;
+					front.prev = newNode;
+					front = newNode;
+				}
+
+				Size++;
+			}
+		}
+
+		void insertRear(char data){
+			Node newNode = Node.getnode(data);
+
+			if (newNode == null)
+				System.out.print("OverFlow\n");
+			else {
+				if (rear == null)
+					front = rear = newNode;
+				else {
+					newNode.prev = rear;
+					rear.next = newNode;
+					rear = newNode;
+				}
+
+				Size++;
+			}
+		}
+
+		void deleteFront(){
+
+			if (isEmpty())
+				System.out.print("UnderFlow\n");
+			else {
+				Node temp = front;
+				front = front.next;
+
+				if (front == null)
+					rear = null;
+				else
+					front.prev = null;
+
+				Size--;
+			}
+		}
+
+		void deleteRear(){
+
+			if (isEmpty())
+				System.out.print("UnderFlow\n");
+			else {
+				Node temp = rear;
+				rear = rear.prev;
+
+				if (rear == null)
+					front = null;
+				else
+					rear.next = null;
+
+				Size--;
+			}
+		}
+
+		char getFront(){
+			if (isEmpty())
+				return '0';
+			return front.data;
+		}
+
+		char getRear(){
+			if (isEmpty())
+				return '0';
+			return rear.data;
+		}
+
+		void erase(){
+			rear = null;
+			while (front != null) {
+				Node temp = front;
+				front = front.next;
+			}
+			Size = 0;
+		}
+	}
+
+	public static void main(String[] args){
+		Deque dq = new Deque();
+		dq.insertFront('E');
+		dq.insertFront('A');
+		dq.insertRear('s');
+		System.out.println(dq.getFront());
+		dq.insertFront('Y');
+		System.out.println(dq.getFront());
+		dq.insertFront('Q');
+		dq.insertFront('U');
+		dq.insertFront('E');
+		System.out.println(dq.getRear());
+		System.out.println(dq.getRear());
+		System.out.println(dq.getFront());
+		dq.insertRear('s');
+		dq.insertRear('t');
+		System.out.println(dq.getFront());
+		System.out.println(dq.getRear());
+		System.out.println(dq.getFront());
+		dq.insertFront('I');
+		dq.insertFront('O');
+		System.out.println(dq.getRear());
+		dq.insertRear('n');
+		System.out.println(dq.getFront());
+		System.out.println(dq.getFront());
+		System.out.println(dq.getRear());
+	}
+}
+