Insert the following values into an initially empty BST:

Example 1:  4  2  6  5  1  7  3
                                        
                4                       
               / \                      
              /   \                     
             2     6                    
            / \   / \                   
           1   3 5   7                  
                                        
                                        
                                        
                                        
                                        
                                        
Example 2:  5  6  2  3  4  7  1
                                        
               5                        
              / \                       
             /   \                      
            2     6                     
           / \     \                    
          1   3     7                   
               \                        
                4                       
                                        
                                        
                                        
                                        
Example 3:  1  2  3  4  5  6  7
                                        
          1                             
           \                            
            2                           
             \                          
              3                         
               \                        
                4                       
                 \                      
                  5                     
                   \                    
                    6                   
                     \                  
                      7