diff --git a/.gitignore b/.gitignore
index 32858aa..628792e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,6 +3,10 @@
# Mobile Tools for Java (J2ME)
.mtj.tmp/
+build/*
+.gradle/*
+*.iml
+
# Package Files #
*.jar
*.war
diff --git a/build.gradle b/build.gradle
new file mode 100644
index 0000000..c33546c
--- /dev/null
+++ b/build.gradle
@@ -0,0 +1,14 @@
+group 'org'
+version '1.0-SNAPSHOT'
+
+apply plugin: 'java'
+
+repositories {
+ mavenCentral()
+}
+
+dependencies {
+ compile 'org.jetbrains:annotations:15.0'
+ compile 'com.googlecode.json-simple:json-simple:1.1'
+ testCompile group: 'junit', name: 'junit', version: '4.12'
+}
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..0c19db4
--- /dev/null
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,6 @@
+#Sun Feb 14 15:03:16 MSK 2016
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-2.5-bin.zip
diff --git a/gradlew b/gradlew
new file mode 100755
index 0000000..91a7e26
--- /dev/null
+++ b/gradlew
@@ -0,0 +1,164 @@
+#!/usr/bin/env bash
+
+##############################################################################
+##
+## Gradle start up script for UN*X
+##
+##############################################################################
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn ( ) {
+ echo "$*"
+}
+
+die ( ) {
+ echo
+ echo "$*"
+ echo
+ exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+case "`uname`" in
+ CYGWIN* )
+ cygwin=true
+ ;;
+ Darwin* )
+ darwin=true
+ ;;
+ MINGW* )
+ msys=true
+ ;;
+esac
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched.
+if $cygwin ; then
+ [ -n "$JAVA_HOME" ] && JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+fi
+
+# 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\"`/" >&-
+APP_HOME="`pwd -P`"
+cd "$SAVED" >&-
+
+CLASSPATH=$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" ] ; 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, switch paths to Windows format before running java
+if $cygwin ; then
+ APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+ CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+
+ # 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`="\"$arg\""
+ fi
+ i=$((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
+
+# Split up the JVM_OPTS And GRADLE_OPTS values into an array, following the shell quoting and substitution rules
+function splitJvmOpts() {
+ JVM_OPTS=("$@")
+}
+eval splitJvmOpts $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS
+JVM_OPTS[${#JVM_OPTS[*]}]="-Dorg.gradle.appname=$APP_BASE_NAME"
+
+exec "$JAVACMD" "${JVM_OPTS[@]}" -classpath "$CLASSPATH" org.gradle.wrapper.GradleWrapperMain "$@"
diff --git a/gradlew.bat b/gradlew.bat
new file mode 100644
index 0000000..aec9973
--- /dev/null
+++ b/gradlew.bat
@@ -0,0 +1,90 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windowz variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+if "%@eval[2+2]" == "4" goto 4NT_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+goto execute
+
+:4NT_args
+@rem Get arguments from the 4NT Shell from JP Software
+set CMD_LINE_ARGS=%$
+
+: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 0000000..bd29227
--- /dev/null
+++ b/settings.gradle
@@ -0,0 +1,2 @@
+rootProject.name = 'hw02'
+
diff --git a/src/main/java/sp/StreamSerializable.java b/src/main/java/sp/StreamSerializable.java
new file mode 100644
index 0000000..4ea7dcb
--- /dev/null
+++ b/src/main/java/sp/StreamSerializable.java
@@ -0,0 +1,15 @@
+package sp;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+public interface StreamSerializable {
+
+ void serialize(OutputStream out) throws IOException;
+
+ /**
+ * Replace current state with data from input stream
+ */
+ void deserialize(InputStream in) throws IOException;
+}
\ No newline at end of file
diff --git a/src/main/java/sp/Trie.java b/src/main/java/sp/Trie.java
new file mode 100644
index 0000000..4ebfd31
--- /dev/null
+++ b/src/main/java/sp/Trie.java
@@ -0,0 +1,32 @@
+package sp;
+
+public interface Trie {
+
+ /**
+ * Expected complexity: O(|element|)
+ * @return true if this set did not already contain the specified
+ * element
+ */
+ boolean add(String element);
+
+ /**
+ * Expected complexity: O(|element|)
+ */
+ boolean contains(String element);
+
+ /**
+ * Expected complexity: O(|element|)
+ * @return true if this set contained the specified element
+ */
+ boolean remove(String element);
+
+ /**
+ * Expected complexity: O(1)
+ */
+ int size();
+
+ /**
+ * Expected complexity: O(|prefix|)
+ */
+ int howManyStartsWithPrefix(String prefix);
+}
\ No newline at end of file
diff --git a/src/main/java/sp/TrieImpl.java b/src/main/java/sp/TrieImpl.java
new file mode 100644
index 0000000..9ea972d
--- /dev/null
+++ b/src/main/java/sp/TrieImpl.java
@@ -0,0 +1,208 @@
+package sp;
+
+import java.io.*;
+import java.lang.Character;
+import java.lang.ref.WeakReference;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.json.simple.JSONObject;
+import org.json.simple.JSONValue;
+
+public class TrieImpl implements Trie, StreamSerializable {
+
+ private final Node root = new Node();
+
+ @Override
+ public boolean add(String element) {
+ Node node = root;
+ for (char c : element.toCharArray()) {
+ node = node.getNextNodeOrCreateIfNotExists(c);
+ }
+ return changeLeafState(node, true);
+ }
+
+ @Override
+ public boolean contains(String element) {
+ Node node = findNode(element);
+ return node != null && node.isLeaf();
+ }
+
+ @Override
+ public boolean remove(String element) {
+ Node node = findNode(element);
+ return node != null && changeLeafState(node, false);
+ }
+
+ @Override
+ public int size() {
+ return root.getSize();
+ }
+
+ @Override
+ public int howManyStartsWithPrefix(String prefix) {
+ Node node = findNode(prefix);
+ return node == null ? 0 : node.getSize();
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ return obj instanceof TrieImpl && root.equals(((TrieImpl) obj).root);
+ }
+
+ @Override
+ public int hashCode() {
+ return root.hashCode();
+ }
+
+ @Override
+ public void serialize(OutputStream out) throws IOException {
+ JSONObject obj = root.toJson();
+ out.write(obj.toJSONString().getBytes());
+ }
+
+ @Override
+ public void deserialize(InputStream in) throws IOException {
+ try {
+ JSONObject obj = (JSONObject) JSONValue.parseWithException(new InputStreamReader(in));
+ root.fromJson(obj, null);
+ } catch (Exception e) {
+ throw new IOException("can't parse json", e);
+ }
+ }
+
+ private Node findNode(String element) {
+ Node node = root;
+ for (char c : element.toCharArray()) {
+ if (!node.containsKey(c)) return null;
+ node = node.get(c);
+ }
+ return node;
+ }
+
+ private boolean changeLeafState(Node node, boolean value) {
+ if (node.isLeaf() == value) return false;
+ node.setLeaf(value);
+
+ int delta = value ? 1 : -1;
+ for (Node prev = null; node != null; node = node.getParent()) {
+ if (prev != null && prev.getSize() == 0) {
+ node.remove(prev.character);
+ }
+ node.setSize(node.getSize() + delta);
+ prev = node;
+ }
+
+ return true;
+ }
+
+ private static class Node {
+
+ private int wordCount = 0;
+ private boolean isLeaf = false;
+ private char character = '\n';
+ private WeakReference parent = null;
+ private Map nextNodes = new HashMap<>();
+
+ public static final String WORD_COUNT = "wordCount";
+ public static final String CHARACTER = "character";
+ public static final String IS_LEAF = "isLeaf";
+ public static final String OTHER = "other";
+
+ public Node() {
+ }
+
+ private Node(Node prev, char c) {
+ parent = new WeakReference<>(prev);
+ character = c;
+ }
+
+ public Node get(char key) {
+ return nextNodes.get(key);
+ }
+
+ public Node remove(char key) {
+ return nextNodes.remove(key);
+ }
+
+ public boolean containsKey(char key) {
+ return nextNodes.containsKey(key);
+ }
+
+ public void put(char key, Node value) {
+ nextNodes.put(key, value);
+ }
+
+ @Override
+ public boolean equals(Object o) {
+ if (!(o instanceof Node)) return false;
+ Node other = (Node) o;
+ return wordCount == other.wordCount &&
+ isLeaf == other.isLeaf &&
+ character == other.character &&
+ nextNodes.keySet().equals(other.nextNodes.keySet()) &&
+ nextNodes.equals(other.nextNodes);
+ }
+
+ @Override
+ public int hashCode() {
+ return nextNodes.hashCode() + (isLeaf ? 1 : 0);
+ }
+
+ public void fromJson(JSONObject obj, Node prev) throws Exception {
+ parent = prev == null ? null : new WeakReference<>(prev);
+ wordCount = ((Long) obj.get(WORD_COUNT)).intValue();
+ isLeaf = (Boolean) obj.get(IS_LEAF);
+ character = ((String) obj.get(CHARACTER)).charAt(0);
+ JSONObject other = (JSONObject) obj.get(OTHER);
+ nextNodes.clear();
+ for (Object key : other.keySet()) {
+ Node node = new Node();
+ node.fromJson((JSONObject) other.get(key), this);
+ put(node.character, node);
+ }
+ }
+
+ @SuppressWarnings("unchecked")
+ public JSONObject toJson() {
+ JSONObject obj = new JSONObject();
+ obj.put(WORD_COUNT, wordCount);
+ obj.put(IS_LEAF, isLeaf);
+ obj.put(CHARACTER, Character.toString(character));
+ JSONObject other = new JSONObject();
+ for (Map.Entry entry : nextNodes.entrySet()) {
+ other.put(entry.getKey(), entry.getValue().toJson());
+ }
+ obj.put(OTHER, other);
+ return obj;
+ }
+
+ public Node getNextNodeOrCreateIfNotExists(char key) {
+ if (!containsKey(key)) {
+ put(key, new Node(this, key));
+ }
+ return get(key);
+ }
+
+ public int getSize() {
+ return wordCount;
+ }
+
+ public void setSize(int count) {
+ wordCount = count;
+ }
+
+ public Node getParent() {
+ return parent == null ? null : parent.get();
+ }
+
+ public boolean isLeaf() {
+ return isLeaf;
+ }
+
+ public void setLeaf(boolean value) {
+ isLeaf = value;
+ }
+
+ }
+}
\ No newline at end of file
diff --git a/src/test/java/sp/TrieTest.java b/src/test/java/sp/TrieTest.java
new file mode 100644
index 0000000..78f1749
--- /dev/null
+++ b/src/test/java/sp/TrieTest.java
@@ -0,0 +1,232 @@
+package sp;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.InputStream;
+
+import static org.junit.Assert.*;
+
+public class TrieTest {
+
+ @org.junit.Test
+ public void testSerialize() throws Exception {
+ TrieImpl trie = new TrieImpl();
+ TrieImpl other = new TrieImpl();
+
+ other.add("");
+ other.add("aa");
+
+ trie.add("");
+ trie.add("aa");
+
+ assertTrue(trie.equals(other));
+
+ trie.add("a");
+ trie.add("aaa");
+ trie.add("aab");
+ trie.add("aac");
+ trie.add("ab");
+
+ assertFalse(trie.equals(other));
+
+ ByteArrayOutputStream out = new ByteArrayOutputStream();
+ trie.serialize(out);
+ InputStream in = new ByteArrayInputStream(out.toByteArray());
+ other.deserialize(in);
+
+
+ assertTrue(trie.equals(other));
+
+ }
+
+ @org.junit.Test
+ public void testAdd() throws Exception {
+ Trie trie = new TrieImpl();
+
+ assertTrue(trie.add(""));
+ assertTrue(trie.add("aa"));
+ assertTrue(trie.add("a"));
+ assertTrue(trie.add("aaa"));
+ assertTrue(trie.add("aab"));
+ assertTrue(trie.add("aac"));
+ assertTrue(trie.add("ab"));
+
+ assertFalse(trie.add(""));
+ assertFalse(trie.add("aa"));
+ assertFalse(trie.add("a"));
+ assertFalse(trie.add("aaa"));
+ assertFalse(trie.add("aab"));
+ assertFalse(trie.add("aac"));
+ assertFalse(trie.add("ab"));
+
+ trie.remove("");
+ trie.remove("aab");
+
+ assertTrue(trie.add("aaaa"));
+ assertFalse(trie.add("aaaa"));
+
+ trie.remove("a");
+ trie.remove("aa");
+ trie.remove("aaa");
+ trie.remove("aac");
+ trie.remove("ab");
+ }
+
+ @org.junit.Test
+ public void testRemove() throws Exception {
+ Trie trie = new TrieImpl();
+ assertFalse(trie.contains(""));
+ trie.add("");
+ trie.add("aa");
+ trie.add("a");
+ trie.add("aaa");
+ trie.add("aab");
+ trie.add("aac");
+ trie.add("ab");
+ assertTrue(trie.remove(""));
+ assertTrue(trie.remove("aab"));
+ trie.add("aaaa");
+ assertTrue(trie.remove("a"));
+ assertTrue(trie.remove("aa"));
+ assertTrue(trie.remove("aaa"));
+ assertTrue(trie.remove("aac"));
+ assertTrue(trie.remove("ab"));
+
+ assertFalse(trie.remove(""));
+ assertFalse(trie.remove("aab"));
+ assertFalse(trie.remove(""));
+ assertFalse(trie.remove("aab"));
+ assertFalse(trie.remove("a"));
+ assertFalse(trie.remove("aa"));
+ assertFalse(trie.remove("aaa"));
+ assertFalse(trie.remove("aac"));
+ assertFalse(trie.remove("ab"));
+ }
+
+ @org.junit.Test
+ public void testContains() throws Exception {
+ Trie trie = new TrieImpl();
+ assertFalse(trie.contains(""));
+ trie.add("");
+ trie.add("aa");
+ trie.add("a");
+ trie.add("aaa");
+ trie.add("aab");
+ trie.add("aac");
+ trie.add("ab");
+
+ assertTrue(trie.contains(""));
+ assertTrue(trie.contains("aa"));
+ assertTrue(trie.contains("a"));
+ assertTrue(trie.contains("aaa"));
+ assertTrue(trie.contains("aab"));
+ assertTrue(trie.contains("aac"));
+ assertTrue(trie.contains("ab"));
+
+ trie.remove("");
+ trie.remove("aab");
+
+ assertFalse(trie.contains(""));
+ assertTrue(trie.contains("aa"));
+ assertTrue(trie.contains("a"));
+ assertTrue(trie.contains("aaa"));
+ assertFalse(trie.contains("aab"));
+ assertTrue(trie.contains("aac"));
+ assertTrue(trie.contains("ab"));
+
+ trie.add("aaaa");
+ trie.remove("a");
+ trie.remove("aa");
+ trie.remove("aaa");
+ trie.remove("aac");
+ trie.remove("ab");
+
+ assertFalse(trie.contains(""));
+ assertFalse(trie.contains("aa"));
+ assertFalse(trie.contains("a"));
+ assertFalse(trie.contains("aaa"));
+ assertFalse(trie.contains("aab"));
+ assertFalse(trie.contains("aac"));
+ assertFalse(trie.contains("ab"));
+ assertTrue(trie.contains("aaaa"));
+ }
+
+ @org.junit.Test
+ public void testSize() throws Exception {
+ Trie trie = new TrieImpl();
+
+ assertEquals(trie.size(), 0);
+ trie.add("");
+ assertEquals(trie.size(), 1);
+ trie.add("aa");
+ trie.add("a");
+ trie.add("aaa");
+ assertEquals(trie.size(), 4);
+ trie.add("aab");
+ trie.add("aac");
+ trie.add("ab");
+ assertEquals(trie.size(), 7);
+
+ trie.remove("");
+ trie.remove("aab");
+ assertEquals(trie.size(), 5);
+
+ trie.add("aaaa");
+ assertEquals(trie.size(), 6);
+
+ trie.remove("a");
+ trie.remove("aa");
+ trie.remove("aaa");
+ assertEquals(trie.size(), 3);
+ trie.remove("aac");
+ trie.remove("ab");
+ assertEquals(trie.size(), 1);
+
+ }
+
+ @org.junit.Test
+ public void testHowManyStartsWithPrefix() throws Exception {
+ Trie trie = new TrieImpl();
+
+ assertEquals(trie.howManyStartsWithPrefix(""), 0);
+ assertEquals(trie.howManyStartsWithPrefix("a"), 0);
+ assertEquals(trie.howManyStartsWithPrefix("aa"), 0);
+ assertEquals(trie.howManyStartsWithPrefix("aaa"), 0);
+
+ trie.add("");
+ trie.add("aa");
+ trie.add("a");
+ trie.add("aaa");
+ trie.add("aab");
+ trie.add("aac");
+ trie.add("ab");
+
+ assertEquals(trie.howManyStartsWithPrefix(""), 7);
+ assertEquals(trie.howManyStartsWithPrefix("a"), 6);
+ assertEquals(trie.howManyStartsWithPrefix("aa"), 4);
+ assertEquals(trie.howManyStartsWithPrefix("aaa"), 1);
+
+ trie.remove("");
+ trie.remove("aab");
+
+ trie.add("aaaa");
+
+ assertEquals(trie.howManyStartsWithPrefix(""), 6);
+ assertEquals(trie.howManyStartsWithPrefix("a"), 6);
+ assertEquals(trie.howManyStartsWithPrefix("aa"), 4);
+ assertEquals(trie.howManyStartsWithPrefix("aaa"), 2);
+
+ trie.remove("a");
+ trie.remove("aa");
+ trie.remove("aaa");
+ trie.remove("aac");
+ trie.remove("ab");
+
+ assertEquals(trie.howManyStartsWithPrefix(""), 1);
+ assertEquals(trie.howManyStartsWithPrefix("a"), 1);
+ assertEquals(trie.howManyStartsWithPrefix("aa"), 1);
+ assertEquals(trie.howManyStartsWithPrefix("aaa"), 1);
+ }
+
+
+}
\ No newline at end of file