APPEND NODE AT TAIL OF LL

 */
SinglyLinkedListNode* insertNodeAtTail(SinglyLinkedListNode* head, int data) {
	
    SinglyLinkedListNode* new_node = (SinglyLinkedListNode*)malloc(sizeof(SinglyLinkedListNode));
    new_node->data = data;

    if(head==NULL)
       return new_node;

    SinglyLinkedListNode*temp=head;
    while(temp->next!=NULL)
    {
      temp=temp->next;

    }   

    temp->next=new_node;
    return head;

}