public class IntTree {
    private IntTreeNode root;
    /* IntTreeNode has (1) data, (2) left, (3) right */

    public IntTree() {
        this.root = new IntTreeNode(0, new IntTreeNode(1, new IntTreeNode(2),
                null), new IntTreeNode(3, null, new IntTreeNode(4)));
    }
    
    public boolean contains(int value) {
        return contains(this.root, value);
    }
    private boolean contains(IntTreeNode current, int value) {
       if (current == null) {
           return false;
       }
       else if (current.data == value) {
           return true;
       }
       
       else {
           // current.left
           boolean containedLeft = contains(current.left, value);
           // current.right
           boolean containedRight = contains(current.right, value);
           return containedLeft || containedRight;
       }
    }

    public void print() {
        print(this.root);
    }

    private void print(IntTreeNode current) {
        if (current != null) {
            System.out.print(current.data + " ");
            print(current.left);
            print(current.right);
        }
    }
}

// [0] -> ([1] -> [2])
// print root