Merge pull request #711 from ojasiiitd/patch-1

Updated StackOfLinkedList.java

DataStructures/Stacks/StackOfLinkedList.java

@@ -1,7 +1,5 @@
 /**
- *
  * @author Varun Upadhyay (https://github.com/varunu28)
- *
  */
 
 // An implementation of a Stack using a Linked List
@@ -25,9 +23,7 @@ class StackOfLinkedList {
         stack.pop();
 
         System.out.println("Top element of stack currently is: " + stack.peek());
-
     }
-
 }
 
 // A node class
@@ -44,66 +40,71 @@ class Node {
 
 /**
  * A class which implements a stack using a linked list
- *
+ * <p>
  * Contains all the stack methods : push, pop, printStack, isEmpty
  **/
 
 class LinkedListStack {
 
     Node head = null;
-    int size = 0;
 
     public void push(int x) {
         Node n = new Node(x);
-        if (getSize() == 0) {
+        if (head == null) {
             head = n;
-        }
+        } else {
-        else {
             Node temp = head;
             n.next = temp;
             head = n;
         }
-        size++;
     }
 
     public void pop() {
-        if (getSize() == 0) {
+        if (head == null) {
             System.out.println("Empty stack. Nothing to pop");
         }
 
         Node temp = head;
         head = head.next;
-        size--;
-
         System.out.println("Popped element is: " + temp.data);
     }
 
     public int peek() {
-      if (getSize() == 0) {
+        if (head == null) {
-        return -1;
+            return -1;
-      }
+        }
-
+        return head.data;
-      return head.data;
     }
 
     public void printStack() {
-
         Node temp = head;
         System.out.println("Stack is printed as below: ");
         while (temp != null) {
-            System.out.println(temp.data + " ");
+            if (temp.next == null) {
+                System.out.print(temp.data);
+            } else {
+                System.out.print(temp.data + " -> ");
+            }
             temp = temp.next;
         }
         System.out.println();
-
     }
 
     public boolean isEmpty() {
-        return getSize() == 0;
+        return head == null;
     }
 
     public int getSize() {
-        return size;
+        if (head == null)
+            return 0;
+        else {
+            int size = 1;
+            Node temp = head;
+            while (temp.next != null) {
+                temp = temp.next;
+                size++;
+            }
+            return size;
+        }
     }
-
 }