merge two linked list alternatively: done

Author: Ram swaroop

src/me/ramswaroop/linkedlists/MergeTwoLinkedListAlternatively.java

@@ -0,0 +1,74 @@
+package me.ramswaroop.linkedlists;
+
+import me.ramswaroop.common.SingleLinkedList;
+import me.ramswaroop.common.SingleLinkedNode;
+
+/**
+ * Created by IntelliJ IDEA.
+ *
+ * @author: ramswaroop
+ * @date: 7/13/15
+ * @time: 12:54 PM
+ */
+public class MergeTwoLinkedListAlternatively {
+
+    /**
+     * Given two linked lists, insert nodes of second list into first list at
+     * alternate positions of first list till there are no more positions to
+     * insert in first list.
+     * <p/>
+     * Example,
+     * Input:   L1: 5->7->17->13->11 and L2: 12->10->2->4->6
+     * Output:  L1: 5->12->7->10->17->2->13->4->11->6 and L2: empty
+     * <p/>
+     * Input:   L1: 1->2->3 and L2: 4->5->6->7->8
+     * Output:  L1: 1->4->2->5->3->6 and L2: 7->8
+     *
+     * @param node1
+     * @param node2
+     * @param <E>
+     * @return
+     */
+    public static <E extends Comparable<E>> SingleLinkedNode<E> mergeTwoLinkedListAlternatively(SingleLinkedNode<E> node1,
+                                                                                                SingleLinkedNode<E> node2) {
+
+        SingleLinkedNode<E> curr1 = node1, curr2 = node2, temp1, temp2;
+
+        while (curr1 != null && curr2 != null) {
+            temp1 = curr1.next;
+            temp2 = curr2.next;
+
+            curr1.next = curr2;
+            curr2.next = temp1;
+
+            curr1 = temp1;
+            curr2 = temp2;
+        }
+
+        return curr2;
+
+    }
+
+    public static void main(String a[]) {
+        SingleLinkedList<Integer> linkedList1 = new SingleLinkedList<>();
+        linkedList1.add(00);
+        linkedList1.add(11);
+        linkedList1.add(22);
+        linkedList1.add(33);
+        linkedList1.add(44);
+        linkedList1.add(55);
+        linkedList1.printList();
+        SingleLinkedList<Integer> linkedList2 = new SingleLinkedList<>();
+        linkedList2.add(21);
+        linkedList2.add(33);
+        linkedList2.add(44);
+        linkedList2.add(55);
+        linkedList2.add(67);
+        linkedList2.add(89);
+        linkedList2.add(99);
+        linkedList2.printList();
+        SingleLinkedNode<Integer> list2 = mergeTwoLinkedListAlternatively(linkedList1.head, linkedList2.head);
+        linkedList1.printList();
+        SingleLinkedList.printList(list2);
+    }
+}