AVL Tree Implementation

Source Code:
Github: AVLTree.java

Output:

        Insert 19
19 
    
   23       
  / \   
 /   \  
 19   34   
/       
12       
                
   23       
  / \   
 /   \  
 12   34   
/ \     
6 19     
                
       23               
      / \       
     /   \      
    /     \     
   /       \    
   12       34       
  / \     / \   
 /   \   /   \  
 6   19   31   60   
  \             
  9             
                                
       23               
      / \       
     /   \      
    /     \     
   /       \    
   12       34       
  / \     / \   
 /   \   /   \  
 6   19   31   60   
  \ /           
  9 14