void SplayNodeRefresh(SplayTree splay, Tree node) { Compare cmp; AVERT(SplayTree, splay); AVERT(Tree, node); AVER(!SplayTreeIsEmpty(splay)); /* must contain node, at least */ cmp = SplaySplay(splay, splay->nodeKey(node), splay->compare); AVER(cmp == CompareEQUAL); AVER(SplayTreeRoot(splay) == node); splay->updateNode(splay, node); }
Bool SplayTreeInsert(SplayTree splay, Tree node) { Tree neighbour; AVERT(SplayTree, splay); AVERT(Tree, node); AVER(TreeLeft(node) == TreeEMPTY); AVER(TreeRight(node) == TreeEMPTY); if (SplayTreeIsEmpty(splay)) { SplayTreeSetRoot(splay, node); return TRUE; } switch (SplaySplay(splay, splay->nodeKey(node), splay->compare)) { default: NOTREACHED; /* fall through */ case CompareEQUAL: /* duplicate node */ return FALSE; case CompareGREATER: /* left neighbour is at root */ neighbour = SplayTreeRoot(splay); SplayTreeSetRoot(splay, node); TreeSetRight(node, TreeRight(neighbour)); TreeSetLeft(node, neighbour); TreeSetRight(neighbour, TreeEMPTY); break; case CompareLESS: /* right neighbour is at root */ neighbour = SplayTreeRoot(splay); SplayTreeSetRoot(splay, node); TreeSetLeft(node, TreeLeft(neighbour)); TreeSetRight(node, neighbour); TreeSetLeft(neighbour, TreeEMPTY); break; } splay->updateNode(splay, neighbour); splay->updateNode(splay, node); return TRUE; }
Bool SplayTreeDelete(SplayTree splay, Tree node) { Tree leftLast; Compare cmp; AVERT(SplayTree, splay); AVERT(Tree, node); if (SplayTreeIsEmpty(splay)) return FALSE; cmp = SplaySplay(splay, splay->nodeKey(node), splay->compare); AVER(cmp != CompareEQUAL || SplayTreeRoot(splay) == node); if (cmp != CompareEQUAL) { return FALSE; } else if (!TreeHasLeft(node)) { SplayTreeSetRoot(splay, TreeRight(node)); TreeClearRight(node); } else if (!TreeHasRight(node)) { SplayTreeSetRoot(splay, TreeLeft(node)); TreeClearLeft(node); } else { Tree rightHalf = TreeRight(node); TreeClearRight(node); SplayTreeSetRoot(splay, TreeLeft(node)); TreeClearLeft(node); (void)SplaySplay(splay, NULL, compareGreater); leftLast = SplayTreeRoot(splay); AVER(leftLast != TreeEMPTY); AVER(!TreeHasRight(leftLast)); TreeSetRight(leftLast, rightHalf); splay->updateNode(splay, leftLast); } TreeFinish(node); return TRUE; }