Binary Search Tree - Java Snippets _ Dream.in

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print?001 /**

002 *BST.java

003 *

004 *Anunbalancednodebasedbinarysearchtree.Onaverage,operationsareO(log(n)).

005 *RemovingnodescanquicklylinearizethetreesothatsomeoperationsbecomeO(n).

006 *ForO(log(n))operationsintheworstcase,useAVLorRedBlackTrees:{@linkhttp://en.wikipedia.org/wiki/AVL%20tree}.

007 *Inserting,removing,andsearchingrelyonComparable.CompareTo.

008 *

009 *@authorRyanBeckett

010 *@version1.0

011 *JDK1.7

012 *10/16/2011

013 *

014 */

015 publicclassBST



043 }

044 }

045 046 privatevoidinsert(Nodend){

047 if(nd==null)return;

048 if(treeRoot==null){//createtreeroot

049 treeRoot=nd;

050 }else{//insertintotree051 insert(treeRoot,nd);

052 }

053 }

054 055 privatevoidinsert(Noderoot,Nodend){

056 if(nd.val.compareTo(root.val)0){063 if(root.right==null){//insertasrightchild

064 root.right=nd;

065 }else{//traverserightsubtree066 insert(root.right,nd);

067 }

068 }

069 }

070 071 /**

072 *Searchforavalueinthetree.073 */

074 publicNodesearch(Tval){

075 returnsearch(treeRoot,val);076 }

077 078 privateNodesearch(Noderoot,Tval){

079 if(root==null)returnnull;080 if(val.compareTo(root.val)0)//traverserightsubtree083 returnsearch(root.right,val);084 else//foundtarget085 returnroot;086 }



087 088 /**

089 *Performaninordertreetraversal.Displaythetreeelementsinascendingorder.

090 */

091 publicvoidprint(){

092 System.out.print("Tree:");

093 if(treeRoot==null){

094 System.out.println();

095 return;

096 }

097 print(treeRoot);

098 System.out.println();

099 }

100 101 privatevoidprint(Noderoot){

102 if(root.left!=null)//traverseleftsubtreefirst

103 print(root.left);

104 System.out.print(root+",");//nowvisitthenode105 if(root.right!=null)

106 print(root.right);//traverserightsubtreeafter

107 }

108 109 /**

110 *Removeavaluefromthetreeandreturnitsnode.111 */

112 publicNoderemove(Tval){

113 returnremove(treeRoot,treeRoot,val);114 }

115 116 privateNoderemove(Noderoot,Nodeparent,Tval){

117 if(root==null)returnnull;//endoftree;targetnotfound118 if(val.compareTo(root.val)0){//traverserightsubtree121 returnremove(root.right,root,val);122 }else{//foundnode;linkroot'sparenttooneofroot'schildren123 adjust(root,parent);

124 returnroot;125 }

126 }

127 128 /**

129 *Removenodebylettingoneofitschildrentakeitsplace.

130 */



131 privatevoidadjust(Noderoot,Nodeparent){

132 //We'reremovingaleaf

133 if(root.left==null&&root.right==null){

134 if(root==treeRoot){//We'reremovingtherootoftree,justclearthetree.

135 treeRoot=null;

136 }elseif(root.val.compareTo(parent.val)



parent.left=root.right;

171 }else{//itisitsparent'srightchild172 parent.right=root.right;

173 }

174 }

175 }

176 }

177 }

178 179 /**

180 *Clearthetree.

181 */

182 publicvoidclear(){

183 treeRoot=null;

184 }

185 186 /*TestDriver*/

187 publicstaticvoidmain(Stringargs[]){

188 189 ///////////////////

190 //Integerexample

191 ///////////////////

192 System.out.println("nIntegerlistexamplen");

193 BSTt=newBST();

194 195 ///////////////////

196 //Inserting

197 ///////////////////

198 t.insert(5);

199 t.insert(2);

200 t.insert(7);

201 t.insert(1);

202 t.insert(5);

203 t.insert(3);

204 t.insert(6);

205 t.insert(10);

206 t.insert(3);

207 t.print();

208 209 ///////////////////

210 //Searching

211 ///////////////////

212 inttarget=10;

213 if(t.search(target)!=null)

214 {



215 System.out.println(target+"wasfound");

216 }else{217 System.out.println(target+"wasnotfound");

218 }

219 target=0;


221 {



225 }

226 target=2;


228 {



232 }

233 234 ///////////////////

235 //Removing

236 ///////////////////

237 System.out.println("Removing11");

238 t.remove(11);

239 t.print();


241 t.remove(5);

242 t.print();


244 t.remove(1);

245 t.print();


247 t.remove(6);

248 t.print();


250 t.remove(10);

251 t.print();


253 t.remove(3);

254 t.print();


256 t.remove(3);

257 t.print();

258 259



260 ///////////////////

261 //Stringexample

262 ///////////////////

263 System.out.println("nnStringlistexamplen");

264 BSTs=newBST();

265 266 ///////////////////

267 //Inserting

268 ///////////////////

269 s.insert("foo");270 s.insert("?>}|");

271 s.insert("bar");272 s.insert("qux");273 s.insert("baz");274 s.insert("?>");

275 s.insert("qux");276 s.print();

277 278 ///////////////////

279 //Searching

280 ///////////////////

281 StringstrTarget="?>}";

282 if(s.search(strTarget)!=null)

283 {

284 System.out.println(strTarget+"wasfound");

285 }else{286 System.out.println(strTarget+"wasnotfound");

287 }

288 strTarget="bar";

289 if(s.search(strTarget)!=null)

290 {

291 System.out.println(strTarget+"wasfound");

292 }else{293 System.out.println(strTarget+"wasnotfound");

294 }

295 296 ///////////////////

297 //Removing

298 ///////////////////

299 System.out.println("Removingbar");

300 s.remove("bar");301 s.print();

302 System.out.println("Removingbaz");

303 s.remove("baz");



304 s.print();

305 System.out.println("Removingqux");

306 s.remove("qux");307 s.print();

308 System.out.println("Removing?>}|");

309 s.remove("?>}|");310 s.print();

311 System.out.println("Removing?>}|");

312 s.remove("?>}|");313 s.print();

314 }

315 }

316 317 classNode

Binary Search Tree - Java Snippets _ Dream.in

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