Singly Linked List operations

LinkedList/src/LinkedList.java

@@ -0,0 +1,90 @@
+/**
+ * Created by ashankar1 on 10/16/15.
+ */
+
+/**
+ * A Singly Linked List node
+ */
+class ListNode{
+    int value;
+    ListNode next;
+
+    ListNode(int val){
+        this.value = val;
+        this.next = null;
+    }
+}
+public class LinkedList {
+    public static void main(String[] args){
+        ListNode head = createList(10);
+        printList(head);
+        System.out.println();
+        findMid(head);
+        ListNode reversedList = reverseList(head);
+        printList(reversedList);
+        System.out.println();
+    }
+
+    /**
+     * Creates a list of n elements
+     * @param n number of elements in the list
+     * @return head of the list
+     */
+    private static ListNode createList(int n) {
+        ListNode head = new ListNode(1);
+        ListNode last = head;
+        for(int i=2;i<n+1;i++){
+            last.next = new ListNode(i);
+            last = last.next;
+        }
+        return head;
+    }
+
+    /**
+     * Prints the linked list
+     * @param head
+     */
+    private static void printList(ListNode head){
+        ListNode current = head;
+        while(current!=null) {
+            System.out.print(current.value+" ");
+            current = current.next;
+        }
+    }
+
+    /**
+     * Reverse the linkedlist
+     * @param head linked list to be reversed
+     * @return head of the reversed linked list
+     */
+    private static ListNode reverseList(ListNode head){
+        ListNode prev = head;
+        ListNode current = head.next;
+        ListNode temp = null;
+        prev.next = null;
+        while(current != null){
+            temp = current.next;
+            current.next = prev;
+            prev = current;
+            current = temp;
+        }
+        return prev;
+    }
+
+    /**
+     * Finds the middle element of the given linked list
+     * @param head linked list
+     * @return the middle node of the linked list
+     */
+    private static ListNode findMid(ListNode head){
+        ListNode slowPtr = head;
+        ListNode fastPtr = head;
+
+        while(fastPtr.next != null && fastPtr.next.next != null){
+            slowPtr = slowPtr.next;
+            fastPtr = fastPtr.next.next;
+        }
+        System.out.println("Mid point "+slowPtr.value);
+        return slowPtr;
+    }
+}