See the following running example to merge linked list into another linked list at alternate positions in java.
package com.ds.linkedlist;
public class MergeAlternateList {
Node head;
public static void main(String[] args) {
MergeAlternateList list1 = new MergeAlternateList();
list1.insert(5);
list1.insert(7);
list1.insert(17);
list1.insert(13);
list1.insert(11);
MergeAlternateList list2 = new MergeAlternateList();
list2.insert(12);
list2.insert(10);
list2.insert(2);
list2.insert(4);
list2.insert(6);
System.out.println("List1: ");
list1.print();
System.out.println("\nList2: ");
list2.print();
MergeAlternateList mlist = new MergeAlternateList();
mlist.mergeAlternateList(list1.head, list2.head);
System.out.println("\nMerged Alternate Lists1 and List2: ");
mlist.print();
}
private void mergeAlternateList(Node list1, Node list2) {
Node l1 = list1, l2 = list2;
Node l1_next = null, l2_next = null;
while(l1 != null && l2 != null){
l1_next = l1.next;
l2_next = l2.next;
l2.next = l1_next;
l1.next = l2;
l1 = l1_next;
l2 = l2_next;
}
this.head = list1;
}
private class Node{
int data;
Node next;
Node(int data){
this.data = data;
}
}
public void insert(int data){
Node newNode = new Node(data);
if(head == null){
head = newNode;
}else{
Node curr = head;
while(curr.next != null){
curr = curr.next;
}
curr.next = newNode;
}
}
public void print(){
if(head==null)
return;
Node curr = head;
while(curr != null){
System.out.print(curr.data + " ");
curr = curr.next;
}
}
}
Output:-
List1:
5 7 17 13 11
List2:
12 10 2 4 6
Merged Alternate Lists1 and List2:
5 12 7 10 17 2 13 4 11 6
