Ik heb een binaire zoekboom gemaakt in C. Het probleem is dat ik kan een efficiënte manier om alle knooppunten met bijvoorbeeld verwijderen niet vinden, id> 5.
Toen ik de boom doorkruisen, als ik een knoop te verwijderen, de recursie wordt steeds fout, omdat de structuur is niet hetzelfde.
Is er een manier, in plaats van het gebruik van een helpende stack naar de gegevens voordat houd ze verwijderen uit de boom?
Hebt u postorder proberen?
Verwijder het knooppunt na zijn kinderen.
Ik zou een inorder wandeling te doen, dit geeft je een orderd lijst van alle items. Dan is de boom weer op te bouwen.
Of als u dit vaak doen, misschien een AVL boom is beter.
Kostas. Je moet meer informatie geven.
Een binaire boom betekent gewoon een boom, waarvan de knooppunten (maximaal) twee kinderen. Gegevens kunnen worden besteld op vele manieren op een dergelijke boom:
Als u ons de code geven, zouden we in staat zijn om meer te helpen.
Ik zal de AVL boom voorkeur voor deze satuation.
Hier is de code te nemen wat je wilt
class BSTree
{
/* */ public static final int INSERT IGNORE = 1;
/* */ public static final int DELETE = -1;
/* */ BTNode root;
/* */ boolean AVL;
/* */ boolean SPL;
/* */ boolean RBL;
/* */ BTNode lastnode;
/* */ int nextside;
/* */
/* */ public BSTree(int mode)
/* */ {
/* 18 */ this.root = null;
/* 19 */ setMode(mode, true);
/* */ }
/* */
/* */ public void setMode(int mode, boolean state) {
/* 23 */ switch (mode)
/* */ {
/* */ case 1:
/* 26 */ if (state == true)
/* */ {
/* 28 */ this.AVL = true;
/* 29 */ this.SPL = false;
/* 30 */ this.RBL = false;
/* */
/* 26 */ return;
/* */ }
/* */
/* 33 */ this.AVL = false;
/* 34 */ break;
/* */ case 2:
/* 37 */ if (state == true)
/* */ {
/* 39 */ this.SPL = true;
/* 40 */ this.AVL = false;
/* 41 */ this.RBL = false;
/* */
/* 37 */ return;
/* */ }
/* */
/* 44 */ this.SPL = false;
/* 45 */ break;
/* */ case 3:
/* 48 */ if (state == true)
/* */ {
/* 50 */ this.RBL = true;
/* 51 */ this.AVL = false;
/* 52 */ this.SPL = false;
/* */
/* 48 */ return;
/* */ }
/* */
/* 55 */ this.RBL = false;
/* 56 */ break;
/* */ default:
/* 59 */ this.AVL = false;
/* 60 */ this.SPL = false;
/* 61 */ this.RBL = false;
/* */ }
/* */ }
/* */
/* */ public boolean isAVL() {
/* 66 */ return this.AVL;
/* */ }
/* */
/* */ public boolean isSPL() {
/* 70 */ return this.SPL;
/* */ }
/* */
/* */ public boolean isRBL() {
/* 74 */ return this.RBL;
/* */ }
/* */
/* */ public BTNode getRoot()
/* */ {
/* 79 */ return this.root;
/* */ }
/* */
/* */ public void setRoot(BTNode node) {
/* 83 */ this.root = node;
/* */ }
/* */
/* */ public boolean isEmpty() {
/* 87 */ return (this.root == null);
/* */ }
/* */
/* */ public int getDepth()
/* */ {
/* 92 */ int maxdepth = 0;
/* 93 */ for (BTNode node = this.root; node != null; node = node.nextPrO())
/* */ {
/* 95 */ int depth = node.getDepth(this.root);
/* 96 */ if (depth > maxdepth)
/* 97 */ maxdepth = depth;
/* */ }
/* 99 */ return maxdepth;
/* */ }
/* */
/* */ public void destroy(BTNode node)
/* */ {
/* 104 */ node = null;
/* */ }
/* */
/* */ public BTNode find(BTData data)
/* */ {
/* 113 */ BTNode node = locate(data);
/* 114 */ if (isSPL())
/* 115 */ splay(this.lastnode);
/* 116 */ return node;
/* */ }
/* */
/* */ public BTNode insert(BTData data) {
/* 120 */ if (isSPL()) {
/* 121 */ return insertSPL(data);
/* */ }
/* 123 */ if (isAVL()) {
/* 124 */ return insertAVL(data);
/* */ }
/* 126 */ if (isRBL()) {
/* 127 */ return insertRBL(data);
/* */ }
/* 129 */ return insertBST(data);
/* */ }
/* */
/* */ public BTNode delete(BTData data, int minmax) {
/* 133 */ if (isAVL()) {
/* 134 */ return deleteAVL(data, minmax);
/* */ }
/* 136 */ if (isSPL()) {
/* 137 */ return deleteSPL(data, minmax);
/* */ }
/* 139 */ if (isRBL()) {
/* 140 */ return deleteRBL(data, minmax);
/* */ }
/* 142 */ return deleteBST(data, minmax);
/* */ }
/* */
/* */ public BTNode locate(BTData data)
/* */ {
/* 150 */ BTNode node = this.root;
/* 151 */ BTNode next = null;
/* 152 */ int side = 0;
/* */
/* 154 */ while (node != null)
/* */ {
/* 156 */ side = node.compareSide(data);
/* 157 */ next = node.getChild(side);
/* 158 */ if (next == node) break; if (next == null)
/* */ break;
/* 160 */ node = next;
/* */ }
/* 162 */ this.lastnode = node;
/* 163 */ this.nextside = side;
/* 164 */ return next;
/* */ }
/* */
/* */ public BTNode add(BTNode node, int side, BTData data)
/* */ {
/* 170 */ BTNode newnode = new BTNode(data);
/* 171 */ link(node, side, newnode);
/* 172 */ return newnode;
/* */ }
/* */
/* */ public BTNode remove(BTNode node)
/* */ {
/* 181 */ BTNode child = node.getChild();
/* 182 */ BTNode parent = node.getParent();
/* 183 */ int side = node.getSide();
/* 184 */ link(parent, side, child);
/* 185 */ destroy(node);
/* 186 */ return parent;
/* */ }
/* */
/* */ public void link(BTNode parent, int side, BTNode child)
/* */ {
/* 193 */ if (child != null)
/* 194 */ child.setParent(parent);
/* 195 */ if (parent != null)
/* 196 */ parent.setChild(side, child);
/* */ else
/* 198 */ this.root = child;
/* */ }
/* */
/* */ public BTNode rotate(BTNode node, int side)
/* */ {
/* 206 */ BTNode parent = node.getParent();
/* 207 */ BTNode child = node.getChild(-side);
/* 208 */ BTNode grand = child.getChild(side);
/* */
/* 210 */ link(node, -side, grand);
/* 211 */ link(parent, node.getSide(), child);
/* 212 */ link(child, side, node);
/* 213 */ return child;
/* */ }
/* */
/* */ public BTNode swap(BTNode node, int minmax)
/* */ {
/* 222 */ BTNode swap = getSuccessor(node, minmax);
/* 223 */ BTNode temp = node;
/* 224 */ swapData(node, swap);
/* 225 */ node = swap;
/* 226 */ swap = temp;
/* 227 */ return node;
/* */ }
/* */
/* */ public BTNode getSuccessor(BTNode node, int minmax) {
/* 231 */ return ((minmax == 1) ? node.prevInO() : node.nextInO());
/* */ }
/* */
/* */ public void swapData(BTNode node1, BTNode node2)
/* */ {
/* 237 */ BTData data = node1.getData();
/* 238 */ node1.setData(node2.getData());
/* 239 */ node2.setData(data);
/* */ }
/* */
/* */ public void deleteAll()
/* */ {
/* 245 */ for (BTNode node = this.root.firstPoO(); node != null; )
/* */ {
/* 247 */ BTNode leaf = node;
/* 248 */ node = leaf.nextPoO();
/* 249 */ destroy(leaf);
/* */ }
/* 251 */ this.root = null;
/* */ }
/* */
/* */ public BTNode locateBST(BTData data)
/* */ {
/* 260 */ for (BTNode node = this.root; node != null; )
/* */ {
/* 262 */ int side = node.compareSide(data);
/* 263 */ if (side == 0)
/* */ break;
/* 265 */ node = node.getChild(side);
/* */ }
/* 267 */ return node;
/* */ }
/* */
/* */ public BTNode insertBST(BTData data)
/* */ {
/* 272 */ if (this.root == null)
/* 273 */ return add(null, 0, data);
/* 274 */ BTNode node = locate(data);
/* 275 */ return ((node != null) ? null : add(this.lastnode, this.nextside, data));
/* */ }
/* */
/* */ public BTNode deleteBST(BTData data, int minmax)
/* */ {
/* 280 */ BTNode node = locate(data);
/* 281 */ if (node == null)
/* 282 */ return null;
/* 283 */ if (node.hasTwoChildren())
/* 284 */ node = swap(node, minmax);
/* 285 */ return remove(node);
/* */ }
/* */
/* */ public BTNode insertAVL(BTData data)
/* */ {
/* 297 */ if (this.root == null)
/* 298 */ return add(null, 0, data);
/* 299 */ if (locate(data) != null)
/* 300 */ return null;
/* 301 */ BTNode node = add(this.lastnode, this.nextside, data);
/* 302 */ rebalanceAVL(this.lastnode, this.nextside, 1);
/* 303 */ return node;
/* */ }
/* */
/* */ public BTNode deleteAVL(BTData data, int minmax)
/* */ {
/* 315 */ BTNode node = locate(data);
/* 316 */ if (node == null) {
/* 317 */ return null;
/* */ }
/* 319 */ if (node.hasTwoChildren()) {
/* 320 */ node = swap(node, minmax);
/* */ }
/* 322 */ int side = node.getSide();
/* 323 */ node = remove(node);
/* 324 */ rebalanceAVL(node, side, -1);
/* 325 */ return node;
/* */ }
/* */
/* */ public void rebalanceAVL(BTNode node, int side, int in)
/* */ {
/* 333 */ for (; node != null; node = node.getParent())
/* */ {
/* 335 */ if (node.getBalance() != in * side)
/* 336 */ node.setBalance(node.getBalance() + in * side);
/* */ else {
/* 338 */ node = rotateAVL(node);
/* */ }
/* 340 */ if ((in == 1) && (node.getBalance() == 0)) return; if ((in == -1) &&
(node.getBalance() != 0))
/* */ return;
/* 342 */ side = node.getSide();
/* */ }
/* */ }
/* */
/* */ public BTNode rotateAVL(BTNode node)
/* */ {
/* 357 */ int side = node.getBalance();
/* 358 */ BTNode child = node.getChild(side);
/* */
/* 360 */ if (child.getBalance() == -side)
/* */ {
/* 362 */ BTNode grand = child.getChild(-side);
/* 363 */ if (grand.getBalance() == -side)
/* */ {
/* 365 */ grand.setBalance(0);
/* 366 */ child.setBalance(side);
/* 367 */ node.setBalance(0);
/* */ }
/* 369 */ else if (grand.getBalance() == side)
/* */ {
/* 371 */ grand.setBalance(0);
/* 372 */ child.setBalance(0);
/* 373 */ node.setBalance(-side);
/* */ }
/* */ else {
/* 376 */ node.setBalance(0);
/* 377 */ child.setBalance(0);
/* */ }
/* 379 */ rotate(child, side);
/* */ }
/* 382 */ else if (child.getBalance() == side)
/* */ {
/* 384 */ node.setBalance(0);
/* 385 */ child.setBalance(0);
/* */ }
/* 387 */ else if (child.getBalance() == 0)
/* */ {
/* 389 */ node.setBalance(side);
/* 390 */ child.setBalance(-side);
/* */ }
/* 392 */ node = rotate(node, -side);
/* 393 */ return node;
/* */ }
/* */
/* */ public void balanceAVL(BTNode node)
/* */ {
/* 400 */ int side = node.getBalance();
/* 401 */ BTNode child = node.getChild(side);
/* 402 */ if (child.getBalance() == -side)
/* */ {
/* 404 */ BTNode grand = child.getChild(-side);
/* 405 */ if (grand.getBalance() == -side)
/* */ {
/* 407 */ grand.setBalance(0);
/* 408 */ child.setBalance(side);
/* 409 */ node.setBalance(0);
/* */ }
/* 411 */ else if (grand.getBalance() == side)
/* */ {
/* 413 */ grand.setBalance(0);
/* 414 */ child.setBalance(0);
/* 415 */ node.setBalance(-side);
/* */ }
/* */ else {
/* 418 */ node.setBalance(0);
/* 419 */ child.setBalance(0);
/* */ }
/* */
/* */ }
/* 423 */ else if (child.getBalance() == side)
/* */ {
/* 425 */ child.setBalance(0);
/* 426 */ node.setBalance(0);
/* */ } else {
/* 428 */ if (child.getBalance() != 0)
/* */ return;
/* 430 */ child.setBalance(-side);
/* */ }
/* */ }
/* */
/* */ public boolean isAVLcompliant(BTNode node)
/* */ {
/* 440 */ boolean balanced = true;
/* */
/* 442 */ if (node == null)
/* 443 */ return true;
/* 444 */ int l = getHeight(node.getChild(-1), 0);
/* 445 */ int r = getHeight(node.getChild(1), 0);
/* 446 */ node.setBalance(r - l);
/* 447 */ if ((r - l > 1) || (r - l < -1))
/* 448 */ balanced = false;
/* 449 */ return ((balanced) && (isAVLcompliant(node.getChild(-1))) && (isAVLcompliant
(node.getChild(1))));
/* */ }
/* */
/* */ public int getHeight(BTNode node, int depth)
/* */ {
/* 454 */ if (node == null)
/* 455 */ return 0;
/* 456 */ if (node.isLeaf()) {
/* 457 */ return (depth + 1);
/* */ }
/* */
/* 460 */ int lmax = getHeight(node.getChild(-1), depth + 1);
/* 461 */ int rmax = getHeight(node.getChild(1), depth + 1);
/* 462 */ return ((lmax > rmax) ? lmax : rmax);
/* */ }
/* */
/* */ public BTNode insertSPL(BTData data)
/* */ {
/* 474 */ if (this.root == null)
/* 475 */ return add(null, 0, data);
/* 476 */ BTNode node = locate(data);
/* 477 */ splay(this.lastnode);
/* 478 */ return ((node != null) ? null : splitinsert(data));
/* */ }
/* */
/* */ public BTNode splitinsert(BTData data)
/* */ {
/* 483 */ BTNode node = new BTNode(data);
/* 484 */ int side = -this.root.compareSide(data);
/* 485 */ BTNode child = this.root.getChild(-side);
/* */
/* 487 */ this.root.setChild(-side, null);
/* 488 */ link(node, side, this.root);
/* 489 */ link(node, -side, child);
/* 490 */ this.root = node;
/* 491 */ return this.root;
/* */ }
/* */
/* */ public BTNode deleteSPL(BTData data, int minmax)
/* */ {
/* 498 */ BTNode node = locate(data);
/* 499 */ splay(this.lastnode);
/* 500 */ if (node == null)
/* 501 */ return null;
/* 502 */ BTNode root = node;
/* 503 */ node = getSuccessor(root, minmax);
/* 504 */ if (node != null)
/* 505 */ splay(node);
/* 506 */ return remove(root);
/* */ }
/* */
/* */ public void splay(BTNode node)
/* */ {
/* 516 */ while (node != this.root)
/* */ {
/* 518 */ BTNode parent = node.getParent();
/* 519 */ BTNode grandparent = parent.getParent();
/* 520 */ int side = node.getSide();
/* 521 */ if (grandparent == null) {
/* 522 */ rotate(parent, -side);
/* */ }
/* 524 */ else if (parent.getSide() == side)
/* */ {
/* 526 */ rotate(grandparent, -side);
/* 527 */ rotate(parent, -side);
/* */ }
/* */ else {
/* 530 */ if (parent.getSide() == side)
/* */ continue;
/* 532 */ rotate(parent, -side);
/* 533 */ rotate(grandparent, side);
/* */ }
/* */ }
/* */ }
/* */
/* */ public boolean isSPLcompliant()
/* */ {
/* 541 */ return true;
/* */ }
/* */
/* */ public BTNode insertRBL(BTData data)
/* */ {
/* 552 */ if (this.root == null)
/* */ {
/* 554 */ this.root = add(null, 0, data);
/* 555 */ this.root.setColor(2);
/* 556 */ return this.root;
/* */ }
/* 558 */ if (locate(data) != null)
/* 559 */ return null;
/* 560 */ BTNode node = add(this.lastnode, this.nextside, data);
/* 561 */ node.setColor(1);
/* 562 */ fixRBinsert(node);
/* 563 */ return node;
/* */ }
/* */
/* */ public void fixRBinsert(BTNode node)
/* */ {
/* 571 */ while (node != this.root)
/* */ {
/* 573 */ BTNode parent = node.getParent();
/* 574 */ if (parent.getColor() == 2)
/* */ break;
/* 576 */ BTNode grandparent = parent.getParent();
/* 577 */ int side = parent.getSide();
/* 578 */ BTNode uncle = grandparent.getChild(-side);
/* 579 */ if ((uncle != null) && (uncle.getColor() == 1))
/* */ {
/* 581 */ parent.setColor(2);
/* 582 */ uncle.setColor(2);
/* 583 */ grandparent.setColor(1);
/* 584 */ node = grandparent;
/* */ }
/* 586 */ else if (node.getSide() == -side)
/* */ {
/* 588 */ rotate(parent, side);
/* 589 */ node = parent;
/* */ } else {
/* 591 */ if (node.getSide() != side)
/* */ continue;
/* 593 */ parent.setColor(2);
/* 594 */ grandparent.setColor(1);
/* 595 */ rotate(grandparent, -side);
/* */ }
/* */ }
/* 598 */ this.root.setColor(2);
/* */ }
/* */
/* */ public BTNode deleteRBL(BTData data, int minmax)
/* */ {
/* 606 */ BTNode node = locate(data);
/* 607 */ if (node == null) {
/* 608 */ return null;
/* */ }
/* 610 */ if (node.hasTwoChildren()) {
/* 611 */ node = swap(node, minmax);
/* */ }
/* 613 */ int color = node.getColor();
/* 614 */ int side = node.getSide();
/* 615 */ node = remove(node);
/* 616 */ if ((this.root != null) && (side == 0)) {
/* 617 */ this.root.setColor(2);
/* */ }
/* 619 */ else if ((node != null) && (color == 2))
/* 620 */ fixRBdelete(node, side);
/* 621 */ return node;
/* */ }
/* */
/* */ public void fixRBdelete(BTNode parent, int side)
/* */ {
/* 629 */ BTNode node = parent.getChild(side);
/* 630 */ if ((node != null) && (node.getColor() == 1))
/* */ {
/* 632 */ node.setColor(2);
/* 633 */ return;
/* */ }
/* */
/* */ do
/* */ {
/* 638 */ if (node != null)
/* */ {
/* 640 */ parent = node.getParent();
/* 641 */ side = node.getSide();
/* */ }
/* 643 */ BTNode sibling = parent.getChild(-side);
/* 644 */ BTNode nephew = sibling.getChild(side);
/* 645 */ BTNode niece = sibling.getChild(-side);
/* */
/* 647 */ if (sibling.getColor() == 1)
/* */ {
/* 649 */ sibling.setColor(2);
/* 650 */ parent.setColor(1);
/* 651 */ rotate(parent, side);
/* */ }
/* 654 */ else if ((isBlack(nephew)) && (isBlack(niece)))
/* */ {
/* 656 */ sibling.setColor(1);
/* 657 */ node = (node == null) ? parent : node.getParent();
/* */ }
/* 660 */ else if ((isBlack(niece)) && (isRed(nephew)))
/* */ {
/* 662 */ sibling.setColor(1);
/* 663 */ nephew.setColor(2);
/* 664 */ rotate(sibling, -side);
/* */ }
/* */ else {
/* 667 */ if (!(isRed(niece)))
/* */ continue;
/* 669 */ sibling.setColor(parent.getColor());
/* 670 */ parent.setColor(2)
;
/* 671 */ niece.setColor(2);
/* 672 */
rotate(parent, side);
/* 673 */
node = this.root;
/* */
}
/* */
}
/* 636 */
while ((node != this.root) && (isBlack(node)));
/* */
/* 676 */ node.setColor(2);
/* */ }
/* */
/* */ public boolean isRed(BTNode node)
/* */ {
/* 681 */
return ((node != null) && (node.getColor() == 1));
/* */
}
/* */
/* */ public boolean isBlack(BTNode node) {
/* 685 */
return ((node == null) || (node.getColor() == 2));
/* */
}
/* */
/* */ public boolean isRBLcompliant(BTNode node)
/* */ {
/* 690 */ return false;
/* */ }
/* */ }
dit is de volledige uitvoering. Veel succes.
Kun je niet navigeren naar het knooppunt en verbinden haar kinderen met de ouders van het knooppunt, zodat u niet de boom te breken? Het idee is om
Omdat het beter wordt uitgelegd op wikipedia , je moet voorzichtig zijn en te bepalen hoeveel kinderen heeft. Daarna is het vrij eenvoudig.