Java Program To Implement Stack Using Linked List
Chapter:
Interview Programs
Last Updated:
30-10-2016 16:27:27 UTC
Program:
/* ............... START ............... */
import java.util.*;
class Node {
protected int data;
protected Node link;
/* Constructor */
public Node() {
link = null;
data = 0;
}
/* Constructor */
public Node(int d, Node n) {
data = d;
link = n;
}
/* Function to set link to next Node */
public void setLink(Node n) {
link = n;
}
/* Function to set data to current Node */
public void setData(int d) {
data = d;
}
/* Function to get link to next node */
public Node getLink() {
return link;
}
/* Function to get data from current Node */
public int getData() {
return data;
}
}
/* Class linkedStack */
class linkedStack {
protected Node top;
protected int size;
/* Constructor */
public linkedStack() {
top = null;
size = 0;
}
/* Function to check if stack is empty */
public boolean isEmpty() {
return top == null;
}
/* Function to get the size of the stack */
public int getSize() {
return size;
}
/* Function to push an element to the stack */
public void push(int data) {
Node nptr = new Node(data, null);
if (top == null)
top = nptr;
else {
nptr.setLink(top);
top = nptr;
}
size++;
}
/* Function to pop an element from the stack */
public int pop() {
if (isEmpty())
throw new NoSuchElementException("Underflow Exception");
Node ptr = top;
top = ptr.getLink();
size--;
return ptr.getData();
}
/* Function to check the top element of the stack */
public int peek() {
if (isEmpty())
throw new NoSuchElementException("Underflow Exception");
return top.getData();
}
/* Function to display the status of the stack */
public void display() {
System.out.print("\nStack = ");
if (size == 0) {
System.out.print("Empty\n");
return;
}
Node ptr = top;
while (ptr != null) {
System.out.print(ptr.getData() + " ");
ptr = ptr.getLink();
}
System.out.println();
}
}
public class JavaStackUsingLinkedList {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
/* Creating object of class linkedStack */
linkedStack ls = new linkedStack();
/* Perform Stack Operations */
System.out.println("Linked Stack Test\n");
char ch;
do {
System.out.println("\nLinked Stack Operations");
System.out.println("1. push");
System.out.println("2. pop");
System.out.println("3. peek");
System.out.println("4. check empty");
System.out.println("5. size");
int choice = scan.nextInt();
switch (choice) {
case 1:
System.out.println("Enter integer element to push");
ls.push(scan.nextInt());
break;
case 2:
try {
System.out.println("Popped Element = " + ls.pop());
} catch (Exception e) {
System.out.println("Error : " + e.getMessage());
}
break;
case 3:
try {
System.out.println("Peek Element = " + ls.peek());
} catch (Exception e) {
System.out.println("Error : " + e.getMessage());
}
break;
case 4:
System.out.println("Empty status = " + ls.isEmpty());
break;
case 5:
System.out.println("Size = " + ls.getSize());
break;
case 6:
System.out.println("Stack = ");
ls.display();
break;
default:
System.out.println("Wrong Entry \n ");
break;
}
/* display stack */
ls.display();
System.out.println("\nDo you want to continue (Type y or n) \n");
ch = scan.next().charAt(0);
} while (ch == 'Y' || ch == 'y');
}
}
/* ............... END ............... */
Output
Linked Stack Test
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
1
Enter integer element to push
5
Stack = 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
1
Enter integer element to push
33
Stack = 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
1
Enter integer element to push
24
Stack = 24 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
1
Enter integer element to push
87
Stack = 87 24 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
1
Enter integer element to push
99
Stack = 99 87 24 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
1
Enter integer element to push
1
Stack = 1 99 87 24 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
5
Size = 6
Stack = 1 99 87 24 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
3
Peek Element = 1
Stack = 1 99 87 24 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
2
Popped Element = 1
Stack = 99 87 24 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
2
Popped Element = 99
Stack = 87 24 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
2
Popped Element = 87
Stack = 24 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
5
Size = 3
Stack = 24 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
2
Popped Element = 24
Stack = 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
3
Peek Element = 33
Stack = 33 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
2
Popped Element = 33
Stack = 5
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
2
Popped Element = 5
Stack = Empty
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
2
Error : Underflow Exception
Stack = Empty
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
3
Error : Underflow Exception
Stack = Empty
Do you want to continue (Type y or n)
y
Linked Stack Operations
1. push
2. pop
3. peek
4. check empty
5. size
4
Empty status = true
Stack = Empty
Do you want to continue (Type y or n)
n
Notes:
-
Two most important operations of Stack
- Push : Push element to beginning of linked list to demonstrate push behavior of stack.
- Pop : We will remove first element of linked list to demonstrate pop behavior of Stack.
Tags
Implement Stack Using Linked List, Java, Interview Programs