diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000000000000000000000000000000000000..7e31822b23d122987551367ca4f2d79afc97c1a6 --- /dev/null +++ b/.gitignore @@ -0,0 +1,216 @@ +# Created by https://www.gitignore.io/api/java,gradle,eclipse,intellij,visualstudiocode +# Edit at https://www.gitignore.io/?templates=java,gradle,eclipse,intellij,visualstudiocode + +### Eclipse ### +.metadata +bin/ +tmp/ +*.tmp +*.bak +*.swp +*~.nib +local.properties +.settings/ +.loadpath +.recommenders + +# External tool builders +.externalToolBuilders/ + +# Locally stored "Eclipse launch configurations" +*.launch + +# PyDev specific (Python IDE for Eclipse) +*.pydevproject + +# CDT-specific (C/C++ Development Tooling) +.cproject + +# CDT- autotools +.autotools + +# Java annotation processor (APT) +.factorypath + +# PDT-specific (PHP Development Tools) +.buildpath + +# sbteclipse plugin +.target + +# Tern plugin +.tern-project + +# TeXlipse plugin +.texlipse + +# STS (Spring Tool Suite) +.springBeans + +# Code Recommenders +.recommenders/ + +# Annotation Processing +.apt_generated/ + +# Scala IDE specific (Scala & Java development for Eclipse) +.cache-main +.scala_dependencies +.worksheet + +### Eclipse Patch ### +# Eclipse Core +.project + +# JDT-specific (Eclipse Java Development Tools) +.classpath + +# Annotation Processing +.apt_generated + +.sts4-cache/ + +### Intellij ### +# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and WebStorm +# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839 + +# User-specific stuff +.idea/**/workspace.xml +.idea/**/tasks.xml +.idea/**/usage.statistics.xml +.idea/**/dictionaries +.idea/**/shelf + +# Generated files +.idea/**/contentModel.xml + +# Sensitive or high-churn files +.idea/**/dataSources/ +.idea/**/dataSources.ids +.idea/**/dataSources.local.xml +.idea/**/sqlDataSources.xml +.idea/**/dynamic.xml +.idea/**/uiDesigner.xml +.idea/**/dbnavigator.xml + +# Gradle +.idea/**/gradle.xml +.idea/**/libraries + +# Gradle and Maven with auto-import +# When using Gradle or Maven with auto-import, you should exclude module files, +# since they will be recreated, and may cause churn. Uncomment if using +# auto-import. +# .idea/modules.xml +# .idea/*.iml +# .idea/modules +# *.iml +# *.ipr + +# CMake +cmake-build-*/ + +# Mongo Explorer plugin +.idea/**/mongoSettings.xml + +# File-based project format +*.iws + +# IntelliJ +out/ + +# mpeltonen/sbt-idea plugin +.idea_modules/ + +# JIRA plugin +atlassian-ide-plugin.xml + +# Cursive Clojure plugin +.idea/replstate.xml + +# Crashlytics plugin (for Android Studio and IntelliJ) +com_crashlytics_export_strings.xml +crashlytics.properties +crashlytics-build.properties +fabric.properties + +# Editor-based Rest Client +.idea/httpRequests + +# Android studio 3.1+ serialized cache file +.idea/caches/build_file_checksums.ser + +### Intellij Patch ### +# Comment Reason: https://github.com/joeblau/gitignore.io/issues/186#issuecomment-215987721 + +# *.iml +# modules.xml +# .idea/misc.xml +# *.ipr + +# Sonarlint plugin +.idea/**/sonarlint/ + +# SonarQube Plugin +.idea/**/sonarIssues.xml + +# Markdown Navigator plugin +.idea/**/markdown-navigator.xml +.idea/**/markdown-navigator/ + +### Java ### +# Compiled class file +*.class + +# Log file +*.log + +# BlueJ files +*.ctxt + +# Mobile Tools for Java (J2ME) +.mtj.tmp/ + +# Package Files # +*.jar +*.war +*.nar +*.ear +*.zip +*.tar.gz +*.rar + +# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml +hs_err_pid* + +### VisualStudioCode ### +.vscode/* +!.vscode/settings.json +!.vscode/tasks.json +!.vscode/launch.json +!.vscode/extensions.json + +### VisualStudioCode Patch ### +# Ignore all local history of files +.history + +### Gradle ### +.gradle +build/ + +# Ignore Gradle GUI config +gradle-app.setting + +# Avoid ignoring Gradle wrapper jar file (.jar files are usually ignored) +!gradle-wrapper.jar + +# Cache of project +.gradletasknamecache + +# # Work around https://youtrack.jetbrains.com/issue/IDEA-116898 +# gradle/wrapper/gradle-wrapper.properties + +### Gradle Patch ### +**/build/ + +# End of https://www.gitignore.io/api/java,gradle,eclipse,intellij,visualstudiocode diff --git a/.vscode/settings.json b/.vscode/settings.json new file mode 100644 index 0000000000000000000000000000000000000000..e0f15db2eb22b5d618150277e48b741f8fdd277a --- /dev/null +++ b/.vscode/settings.json @@ -0,0 +1,3 @@ +{ + "java.configuration.updateBuildConfiguration": "automatic" +} \ No newline at end of file diff --git a/build.gradle b/build.gradle new file mode 100644 index 0000000000000000000000000000000000000000..d986d777691fbe82ab581cb2a0c54c7546a8b5e1 --- /dev/null +++ b/build.gradle @@ -0,0 +1,42 @@ +/* + * This file was generated by the Gradle 'init' task. + * + * This generated file contains a sample Java project to get you started. + * For more details take a look at the Java Quickstart chapter in the Gradle + * User Manual available at https://docs.gradle.org/5.6.1/userguide/tutorial_java_projects.html + */ + +plugins { + // Apply the java plugin to add support for Java + id 'java' + + // Apply the application plugin to add support for building a CLI application + id 'application' +} + +repositories { + // Use jcenter for resolving dependencies. + // You can declare any Maven/Ivy/file repository here. + jcenter() +} + +dependencies { + // This dependency is used by the application. + implementation 'com.google.guava:guava:28.0-jre' + + // Use JUnit Jupiter API for testing. + testImplementation 'org.junit.jupiter:junit-jupiter-api:5.4.2' + + // Use JUnit Jupiter Engine for testing. + testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.4.2' +} + +application { + // Define the main class for the application + mainClassName = 'io.ad.structs.App' +} + +test { + // Use junit platform for unit tests + useJUnitPlatform() +} diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar new file mode 100644 index 0000000000000000000000000000000000000000..490fda8577df6c95960ba7077c43220e5bb2c0d9 Binary files /dev/null and b/gradle/wrapper/gradle-wrapper.jar differ diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties new file mode 100644 index 0000000000000000000000000000000000000000..a4b4429748d92848a3d820c7b099fbeb941066ae --- /dev/null +++ b/gradle/wrapper/gradle-wrapper.properties @@ -0,0 +1,5 @@ +distributionBase=GRADLE_USER_HOME +distributionPath=wrapper/dists +distributionUrl=https\://services.gradle.org/distributions/gradle-6.3-bin.zip +zipStoreBase=GRADLE_USER_HOME +zipStorePath=wrapper/dists diff --git a/gradlew b/gradlew new file mode 100644 index 0000000000000000000000000000000000000000..2fe81a7d95e4f9ad2c9b2a046707d36ceb3980b3 --- /dev/null +++ b/gradlew @@ -0,0 +1,183 @@ +#!/usr/bin/env sh + +# +# Copyright 2015 the original author or authors. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# https://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# + +############################################################################## +## +## Gradle start up script for UN*X +## +############################################################################## + +# Attempt to set APP_HOME +# Resolve links: $0 may be a link +PRG="$0" +# Need this for relative symlinks. +while [ -h "$PRG" ] ; do + ls=`ls -ld "$PRG"` + link=`expr "$ls" : '.*-> \(.*\)$'` + if expr "$link" : '/.*' > /dev/null; then + PRG="$link" + else + PRG=`dirname "$PRG"`"/$link" + fi +done +SAVED="`pwd`" +cd "`dirname \"$PRG\"`/" >/dev/null +APP_HOME="`pwd -P`" +cd "$SAVED" >/dev/null + +APP_NAME="Gradle" +APP_BASE_NAME=`basename "$0"` + +# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. +DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"' + +# Use the maximum available, or set MAX_FD != -1 to use that value. +MAX_FD="maximum" + +warn () { + echo "$*" +} + +die () { + echo + echo "$*" + echo + exit 1 +} + +# OS specific support (must be 'true' or 'false'). +cygwin=false +msys=false +darwin=false +nonstop=false +case "`uname`" in + CYGWIN* ) + cygwin=true + ;; + Darwin* ) + darwin=true + ;; + MINGW* ) + msys=true + ;; + NONSTOP* ) + nonstop=true + ;; +esac + +CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar + +# Determine the Java command to use to start the JVM. +if [ -n "$JAVA_HOME" ] ; then + if [ -x "$JAVA_HOME/jre/sh/java" ] ; then + # IBM's JDK on AIX uses strange locations for the executables + JAVACMD="$JAVA_HOME/jre/sh/java" + else + JAVACMD="$JAVA_HOME/bin/java" + fi + if [ ! -x "$JAVACMD" ] ; then + die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME + +Please set the JAVA_HOME variable in your environment to match the +location of your Java installation." + fi +else + JAVACMD="java" + which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. + +Please set the JAVA_HOME variable in your environment to match the +location of your Java installation." +fi + +# Increase the maximum file descriptors if we can. +if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then + MAX_FD_LIMIT=`ulimit -H -n` + if [ $? -eq 0 ] ; then + if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then + MAX_FD="$MAX_FD_LIMIT" + fi + ulimit -n $MAX_FD + if [ $? -ne 0 ] ; then + warn "Could not set maximum file descriptor limit: $MAX_FD" + fi + else + warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT" + fi +fi + +# For Darwin, add options to specify how the application appears in the dock +if $darwin; then + GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\"" +fi + +# For Cygwin or MSYS, switch paths to Windows format before running java +if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then + APP_HOME=`cygpath --path --mixed "$APP_HOME"` + CLASSPATH=`cygpath --path --mixed "$CLASSPATH"` + JAVACMD=`cygpath --unix "$JAVACMD"` + + # We build the pattern for arguments to be converted via cygpath + ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null` + SEP="" + for dir in $ROOTDIRSRAW ; do + ROOTDIRS="$ROOTDIRS$SEP$dir" + SEP="|" + done + OURCYGPATTERN="(^($ROOTDIRS))" + # Add a user-defined pattern to the cygpath arguments + if [ "$GRADLE_CYGPATTERN" != "" ] ; then + OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)" + fi + # Now convert the arguments - kludge to limit ourselves to /bin/sh + i=0 + for arg in "$@" ; do + CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -` + CHECK2=`echo "$arg"|egrep -c "^-"` ### Determine if an option + + if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then ### Added a condition + eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"` + else + eval `echo args$i`="\"$arg\"" + fi + i=`expr $i + 1` + done + case $i in + 0) set -- ;; + 1) set -- "$args0" ;; + 2) set -- "$args0" "$args1" ;; + 3) set -- "$args0" "$args1" "$args2" ;; + 4) set -- "$args0" "$args1" "$args2" "$args3" ;; + 5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;; + 6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;; + 7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;; + 8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;; + 9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;; + esac +fi + +# Escape application args +save () { + for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done + echo " " +} +APP_ARGS=`save "$@"` + +# Collect all arguments for the java command, following the shell quoting and substitution rules +eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS" + +exec "$JAVACMD" "$@" diff --git a/gradlew.bat b/gradlew.bat new file mode 100644 index 0000000000000000000000000000000000000000..62bd9b9ccefea2b65ae41e5d9a545e2021b90a1d --- /dev/null +++ b/gradlew.bat @@ -0,0 +1,103 @@ +@rem +@rem Copyright 2015 the original author or authors. +@rem +@rem Licensed under the Apache License, Version 2.0 (the "License"); +@rem you may not use this file except in compliance with the License. +@rem You may obtain a copy of the License at +@rem +@rem https://www.apache.org/licenses/LICENSE-2.0 +@rem +@rem Unless required by applicable law or agreed to in writing, software +@rem distributed under the License is distributed on an "AS IS" BASIS, +@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +@rem See the License for the specific language governing permissions and +@rem limitations under the License. +@rem + +@if "%DEBUG%" == "" @echo off +@rem ########################################################################## +@rem +@rem Gradle startup script for Windows +@rem +@rem ########################################################################## + +@rem Set local scope for the variables with windows NT shell +if "%OS%"=="Windows_NT" setlocal + +set DIRNAME=%~dp0 +if "%DIRNAME%" == "" set DIRNAME=. +set APP_BASE_NAME=%~n0 +set APP_HOME=%DIRNAME% + +@rem Resolve any "." and ".." in APP_HOME to make it shorter. +for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi + +@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. +set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m" + +@rem Find java.exe +if defined JAVA_HOME goto findJavaFromJavaHome + +set JAVA_EXE=java.exe +%JAVA_EXE% -version >NUL 2>&1 +if "%ERRORLEVEL%" == "0" goto init + +echo. +echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. +echo. +echo Please set the JAVA_HOME variable in your environment to match the +echo location of your Java installation. + +goto fail + +:findJavaFromJavaHome +set JAVA_HOME=%JAVA_HOME:"=% +set JAVA_EXE=%JAVA_HOME%/bin/java.exe + +if exist "%JAVA_EXE%" goto init + +echo. +echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% +echo. +echo Please set the JAVA_HOME variable in your environment to match the +echo location of your Java installation. + +goto fail + +:init +@rem Get command-line arguments, handling Windows variants + +if not "%OS%" == "Windows_NT" goto win9xME_args + +:win9xME_args +@rem Slurp the command line arguments. +set CMD_LINE_ARGS= +set _SKIP=2 + +:win9xME_args_slurp +if "x%~1" == "x" goto execute + +set CMD_LINE_ARGS=%* + +:execute +@rem Setup the command line + +set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar + +@rem Execute Gradle +"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS% + +:end +@rem End local scope for the variables with windows NT shell +if "%ERRORLEVEL%"=="0" goto mainEnd + +:fail +rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of +rem the _cmd.exe /c_ return code! +if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1 +exit /b 1 + +:mainEnd +if "%OS%"=="Windows_NT" endlocal + +:omega diff --git a/settings.gradle b/settings.gradle new file mode 100644 index 0000000000000000000000000000000000000000..c5d67fc013cd8df2cef45002d85ed532c157fc92 --- /dev/null +++ b/settings.gradle @@ -0,0 +1,10 @@ +/* + * This file was generated by the Gradle 'init' task. + * + * The settings file is used to specify which projects to include in your build. + * + * Detailed information about configuring a multi-project build in Gradle can be found + * in the user manual at https://docs.gradle.org/5.6.1/userguide/multi_project_builds.html + */ + +rootProject.name = 'lists' diff --git a/src/main/java/io/ad/structs/App.java b/src/main/java/io/ad/structs/App.java new file mode 100644 index 0000000000000000000000000000000000000000..010d5418e047d17e31c72333ca040e1011c5c7dd --- /dev/null +++ b/src/main/java/io/ad/structs/App.java @@ -0,0 +1,54 @@ +/* + * This Java source file was generated by the Gradle 'init' task. + */ +package io.ad.structs; + +import java.util.ListIterator; + +public class App { + + + public static void main(String[] args) { + + //Try LinkedList with Iterator + LinkedList<Integer> list = new LinkedList<>(); + list.add(0,1); + list.add(2); + list.add(3); + list.add(3,4); + + for (Integer i : list) + System.out.println(i); + + + + //Try Double-linked List with ListIterator + DoubleLinkedList<Integer> dlist = new DoubleLinkedList<>(); + dlist.add(12); + dlist.add(13); + dlist.add(14); + System.out.println(dlist); + + dlist.remove(0); + System.out.println(dlist); + + ListIterator<Integer> it = dlist.listIterator(); + + while(it.hasNext()) { + System.out.println("hasNext ?: "+it.hasNext()); + System.out.println("hasPrev ?: "+it.hasPrevious()); + System.out.println("NextIndex: "+it.nextIndex()); + System.out.println("PrevIndex: "+it.previousIndex()); + System.out.println("Next-----> "+it.next());; + } + + while(it.hasPrevious()) { + System.out.println("hasNext ?: "+it.hasNext()); + System.out.println("hasPrev ?: "+it.hasPrevious()); + System.out.println("NextIndex: "+it.nextIndex()); + System.out.println("PrevIndex: "+it.previousIndex()); + System.out.println("Previous->"+it.previous()); + } + + } +} diff --git a/src/main/java/io/ad/structs/DoubleLinkedList.java b/src/main/java/io/ad/structs/DoubleLinkedList.java new file mode 100644 index 0000000000000000000000000000000000000000..6ea147fea9c2b54d91bd741aa4bf9bdce3219ea0 --- /dev/null +++ b/src/main/java/io/ad/structs/DoubleLinkedList.java @@ -0,0 +1,254 @@ +package io.ad.structs; + +import java.util.Iterator; +import java.util.ListIterator; +import java.util.NoSuchElementException; + + + +public class DoubleLinkedList<E> implements List<E> { + private ListNode head; + private ListNode last; + private int size; + + // ListNode as member inner class. + private class ListNode { + private ListNode next; + private ListNode prev; + private E data; + + private ListNode(E data, ListNode prev, ListNode next) { + this.data = data; + this.next = next; + this.prev=prev; + } + } + // --------------------------------- + + @Override + public boolean isEmpty() { + return head == null; + } + + @Override + public void add(int index, E element) { + if (element == null) { + throw new NullPointerException("elem must not be null"); + } + if (index < 0) { + throw new IndexOutOfBoundsException(); + } + if (index >= size() + 1) { + throw new IndexOutOfBoundsException(); + } + if (index == 0) { + ListNode newHead = new ListNode(element, null, head); + head = newHead; + if (size()==0) last=newHead; + size++; + return; + } + if (index == size()) { + ListNode temp = new ListNode(element, last, null); + last.next=temp; + last=temp; + size++; + return; + } + + ListNode temp = head; + for (int i = 0; i < index - 1; i++) { + temp = temp.next; + } + ListNode node = new ListNode(element, temp, temp.next); + temp.next.prev=node; + temp.next=node; + size++; + } + + @Override + public void add(E elem) { + if (head == null) { + add(0, elem); + + } else { + add(size, elem); + } + } + + @Override + public int size() { + return size; + } + + @Override + public E get(int index) { + if (index < 0) { + throw new IndexOutOfBoundsException(); + } + if (index >= size()) { + throw new IndexOutOfBoundsException(); + } + if (size() == 0) { + throw new NoSuchElementException(); + } + if (index == size()-1) return last.data; + else { + ListNode temp = head; + for (int i = 0; i < index; i++) { + temp = temp.next; + } + return temp.data; + } + } + + public void addFirst(E elem) { + add(0, elem); + } + + public void addLast(E elem) { + add(size,elem); + } + + public E getFirst() { + return get(0); + } + + public E getLast() { + return get(size() - 1); + } + + public String toString() { + ListNode temp = head; + StringBuilder sb = new StringBuilder("["); + while (temp != null) { + if(sb.length()!=1) sb.append(", "); + sb.append(temp.data); + temp = temp.next; + } + sb.append("]"); + return sb.toString(); + } + + // Iterator as anonymous inner class + + public Iterator<E> iterator() { + return new Iterator<E>() { + ListNode next = DoubleLinkedList.this.head; + public boolean hasNext() { + return next!=null; + } + public E next() { + if (next==null) throw new NoSuchElementException(); + E value = next.data; + next = next.next; + return value; + } + }; + } + + // ListIterator as anonymous inner class + public ListIterator<E> listIterator() { + return new ListIterator<E>() { + + private ListNode next = head; + private ListNode prev = null; + private int nextIndex = 0; + + @Override + public boolean hasNext() { + return next!=null; + } + + @Override + public E next() { + if (hasNext()) { + nextIndex++; + E data = next.data; + next=next.next; + if (prev==null) prev=head; + else prev=prev.next; + return data; + } else { + throw new NoSuchElementException(); + } + } + + @Override + public boolean hasPrevious() { + return prev!=null; + } + + @Override + public E previous() { + if (hasPrevious()) { + nextIndex--; + E data = prev.data; + prev=prev.prev; + if (next==null) next=last; + else next=next.prev; + return data; + } else { + throw new NoSuchElementException(); + } + } + + @Override + public int nextIndex() { + return nextIndex; + } + + @Override + public int previousIndex() { + return nextIndex-1; + } + + @Override + public void remove() { + throw new UnsupportedOperationException(); + + } + + @Override + public void set(E e) { + throw new UnsupportedOperationException(); + + } + + @Override + public void add(E e) { + throw new UnsupportedOperationException(); + + } + + }; + + } + + @Override + public void remove(int index) { + if (index < 0) { + throw new IndexOutOfBoundsException(); + } + if (index >= size()) { + throw new IndexOutOfBoundsException(); + } + if (size() == 0) { + throw new NoSuchElementException(); + } + if (index==0) { + head.next.prev=null; + head = head.next; + if (size()==1) last = null; + } else { + ListNode node = head; + for (int pos = 0; pos<index-1; pos++) { + node=node.next; + } + node.next.next.prev=node; + node.next = node.next.next; + + } + size--; + } +} \ No newline at end of file diff --git a/src/main/java/io/ad/structs/LinkedList.java b/src/main/java/io/ad/structs/LinkedList.java new file mode 100644 index 0000000000000000000000000000000000000000..d9333a13e15c6bd6b084cd1827bdc332762fdafe --- /dev/null +++ b/src/main/java/io/ad/structs/LinkedList.java @@ -0,0 +1,164 @@ +package io.ad.structs; + +import java.util.Iterator; +import java.util.NoSuchElementException; + +public class LinkedList<E> implements List<E> { + private ListNode head; + private ListNode last; + private int size; + + // ListNode as member inner class. + private class ListNode { + private ListNode next; + private E data; + + private ListNode(E data, ListNode next) { + setData(data); + setNext(next); + } + + private void setData(E data) { + this.data = data; + } + + private void setNext(ListNode next) { + this.next = next; + } + } + + @Override + public boolean isEmpty() { + return head == null; + } + + @Override + public void add(int index, E element) { + if (element == null) { + throw new NullPointerException("elem must not be null"); + } + if (index < 0) { + throw new IndexOutOfBoundsException(); + } + if (index >= size() + 1) { + throw new IndexOutOfBoundsException(); + } + if (index == 0) { + ListNode newHead = new ListNode(element, head); + head = newHead; + if (size()==0) last=head; + size++; + return; + } + if (index == size()) { + last.setNext(new ListNode(element, null)); + last=last.next; + size++; + return; + } + + ListNode temp = head; + for (int i = 0; i < index-1; i++) { + temp = temp.next; + } + temp.setNext(new ListNode(element, temp.next)); + size++; + } + + @Override + public void add(E elem) { + add(size, elem); + } + + @Override + public int size() { + return size; + } + + @Override + public E get(int index) { + if (index < 0) { + throw new IndexOutOfBoundsException(); + } + if (index >= size()) { + throw new IndexOutOfBoundsException(); + } + if (size() == 0) { + throw new NoSuchElementException(); + } + ListNode temp = head; + for (int i = 0; i < index; i++) { + temp = temp.next; + } + return temp.data; + } + + public void addFirst(E elem) { + add(0, elem); + } + + public void addLast(E elem) { + add(size,elem); + } + + public E getFirst() { + return get(0); + } + + public E getLast() { + return get(size() - 1); + } + + public String toString() { + ListNode temp = head; + StringBuilder sb = new StringBuilder("["); + while (temp != null) { + if(sb.length()!=1) sb.append(", "); + sb.append(temp.data); + temp = temp.next; + } + sb.append("]"); + return sb.toString(); + } + + // Iterator implemented with anonymous inner class + + public Iterator<E> iterator() { + return new Iterator<E>() { + private ListNode next = LinkedList.this.head; + public boolean hasNext() { + return next!=null; + } + public E next() { + if (next==null) throw new NoSuchElementException(); + E value = next.data; + next = next.next; + return value; + } + }; + } + + @Override + public void remove(int index) { + if (index < 0) { + throw new IndexOutOfBoundsException(); + } + if (index >= size()) { + throw new IndexOutOfBoundsException(); + } + if (size() == 0) { + throw new NoSuchElementException(); + } + if (index==0) { + head = head.next; + } else { + ListNode node = head; + for (int pos = 0; pos<index-1; pos++) { + node=node.next; + } + node.next = node.next.next; + if (index==size()-1) last=node; + } + size--; + } +} \ No newline at end of file diff --git a/src/main/java/io/ad/structs/List.java b/src/main/java/io/ad/structs/List.java new file mode 100644 index 0000000000000000000000000000000000000000..0d616ce3a4a493dc51b9c6f0e30450603c7492a1 --- /dev/null +++ b/src/main/java/io/ad/structs/List.java @@ -0,0 +1,11 @@ +package io.ad.structs; + +public interface List<E> extends Iterable<E> { + + void add(E element); + void add(int index, E element); + int size(); + void remove(int index); + E get(int index); + boolean isEmpty(); +}