summing adult nodes

this competence rudimentary repair - nonetheless i'm perplexing sum together nodes (size ability node class) binary hunt tree. next bst category i have following far, nonetheless advantage 0:

    private enlarged sum(node<t> thisnode)
    {
        (thisnode.left == zero && thisnode.right == null)
            relapse 0;
        (node.right == null)
            relapse sum(thisnode.left);
        (node.left == null) 
            relapse sum(thisnode.right);


        relapse sum(thisnode.left) + sum(thisnode.right);
    }

within node category i have information stores distance name given properties. i'm only perplexing sum whole size. any suggestions ideas?