-
Notifications
You must be signed in to change notification settings - Fork 0
/
Stack implementation using LinkedList.java
71 lines (58 loc) · 1.4 KB
/
Stack implementation using LinkedList.java
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
class Node {
int data;
Node next;
public Node(int data) {
this.data = data;
this.next = null;
}
}
class Stack {
private Node top;
public Stack() {
this.top = null;
}
public boolean isEmpty() {
return top == null;
}
public void push(int data) {
Node newNode = new Node(data);
newNode.next = top;
top = newNode;
}
public int pop() {
if (isEmpty()) {
throw new IllegalStateException("Stack is empty");
}
int data = top.data;
top = top.next;
return data;
}
public int peek() {
if (isEmpty()) {
throw new IllegalStateException("Stack is empty");
}
return top.data;
}
public void display() {
Node current = top;
while (current != null) {
System.out.print(current.data + " -> ");
current = current.next;
}
System.out.println("null");
}
}
public class Main {
public static void main(String[] args) {
Stack stack = new Stack();
stack.push(1);
stack.push(2);
stack.push(3);
System.out.println("Stack:");
stack.display();
System.out.println("Peek: " + stack.peek());
System.out.println("Pop: " + stack.pop());
System.out.println("Stack after pop:");
stack.display();
}
}