rem: if (node->index < x->index)
add: if (node->index <= x->index)
context: static void treeInsert(W_TreeBag *tree, W_Node *node){    W_Node *y = tree->nil;    W_Node *x = tree->root;        while (x != tree->nil) {	y = x;	if (node->index < x->index)	    x = x->left;	else	    x = x->right;    }    node->parent = y;    if (y == tree->nil)	tree->root = node;    else if (node->index < y->index)	y->left = node;    else	y->right = node;}