[数据结构][Tree]Search Binary Tree For Pre Order

public class BinaryTreeNode
{
    public Object data;
    
    public BinaryTreeNode leftPointer;
    
    public BinaryTreeNode rightPointer;
    
    public BinaryTreeNode(Object data)
    {
        this.data = data;
    }
    
}

public class Solution
{
    public void preOrder(BinaryTreeNode node)
    {
        if(node == null)
        {
            return;
        }
        
        visit(node);
        
        if(node.leftPointer != null)
        {
            preOrder(node.leftPointer);
        }
        if(node.rightPointer != null)
        {
            preOrder(node.rightPointer);
        }
    }
    
    public void visit(BinaryTreeNode node)
    {
        System.out.println(node.data);
    }
    
}