Binary Search Tree

BST.java

public class BST {
	static TreeNode bst;
	public static void main(String[] args){
		bst = new TreeNode(10, new TreeNode(9), new TreeNode(11));
		add(12);
		add(1);
		add(3);
		System.out.println(bst);
		remove(1);
		System.out.println(bst);
	}
	
	public static void add(int i){
		TreeNode t = bst;
		while(t != null){
			if(t.item > i){
				if(t.left == null){
					t.left = new TreeNode(i);
					break;
				}
				else t = t.left;
			}
			if(t.item < i){
				if(t.right == null){
					t.right = new TreeNode(i);
					break;
				}
				else t = t.right;
			}
		}
	}
	
	public static void remove(int i){
		TreeNode t = bst;
		while(t != null){
			if(t.left != null && t.item == i){
				t.left = null;
				break;
			}
			if(t.right != null && t.item == i){
				t.right = null;
				break;
			}
			if(t != null && t.item > i){
				t = t.left;
			}
			if(t != null && t.item < i){
				t = t.right;
			}
		}
	}
}

TreeNode.java

public class TreeNode {
	TreeNode left;
	TreeNode right;
	int item;
	
	TreeNode(int i){
		item = i;
	}
	
	TreeNode(int i, TreeNode l, TreeNode r){
		this(i);
		left = l;
		right = r;
	}
	
	@Override
	public String toString(){
		String returnString = "[ ";
		if(left != null) returnString += "left: "+left.toString();
		else returnString += "left: null";
		
		returnString += " item: "+item;
		
		if(right != null) returnString += " right: "+right.toString();
		else returnString += " right: null";
		
		returnString += " ]";
		return returnString;
	}
}