diff --git a/unit5/.idea/.name b/unit5/.idea/.name
deleted file mode 100644
index d377c25..0000000
--- a/unit5/.idea/.name
+++ /dev/null
@@ -1 +0,0 @@
-unit5
\ No newline at end of file
diff --git a/unit5/.idea/compiler.xml b/unit5/.idea/compiler.xml
index 0778677..96cc43e 100644
--- a/unit5/.idea/compiler.xml
+++ b/unit5/.idea/compiler.xml
@@ -17,16 +17,6 @@
       <profile default="true" name="Default" enabled="false">
         <processorPath useClasspath="true" />
       </profile>
-      <profile default="false" name="Maven default annotation processors profile" enabled="true">
-        <sourceOutputDir name="target/generated-sources/annotations" />
-        <sourceTestOutputDir name="target/generated-test-sources/test-annotations" />
-        <outputRelativeToContentRoot value="true" />
-        <processorPath useClasspath="true" />
-        <module name="unit5" />
-      </profile>
     </annotationProcessing>
-    <bytecodeTargetLevel>
-      <module name="unit5" target="1.5" />
-    </bytecodeTargetLevel>
   </component>
 </project>
\ No newline at end of file
diff --git a/unit5/.idea/encodings.xml b/unit5/.idea/encodings.xml
deleted file mode 100644
index b26911b..0000000
--- a/unit5/.idea/encodings.xml
+++ /dev/null
@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="Encoding">
-    <file url="file://$PROJECT_DIR$" charset="UTF-8" />
-  </component>
-</project>
\ No newline at end of file
diff --git a/unit5/.idea/libraries/Maven__junit_junit_3_8_1.xml b/unit5/.idea/libraries/Maven__junit_junit_3_8_1.xml
deleted file mode 100644
index 71b2993..0000000
--- a/unit5/.idea/libraries/Maven__junit_junit_3_8_1.xml
+++ /dev/null
@@ -1,13 +0,0 @@
-<component name="libraryTable">
-  <library name="Maven: junit:junit:3.8.1">
-    <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/junit/junit/3.8.1/junit-3.8.1.jar!/" />
-    </CLASSES>
-    <JAVADOC>
-      <root url="jar://$MAVEN_REPOSITORY$/junit/junit/3.8.1/junit-3.8.1-javadoc.jar!/" />
-    </JAVADOC>
-    <SOURCES>
-      <root url="jar://$MAVEN_REPOSITORY$/junit/junit/3.8.1/junit-3.8.1-sources.jar!/" />
-    </SOURCES>
-  </library>
-</component>
\ No newline at end of file
diff --git a/unit5/.idea/misc.xml b/unit5/.idea/misc.xml
index ddb5070..401d515 100644
--- a/unit5/.idea/misc.xml
+++ b/unit5/.idea/misc.xml
@@ -1,76 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
-  <component name="EntryPointsManager">
-    <entry_points version="2.0" />
-  </component>
-  <component name="MavenProjectsManager">
-    <option name="originalFiles">
-      <list>
-        <option value="$PROJECT_DIR$/pom.xml" />
-      </list>
-    </option>
-  </component>
-  <component name="ProjectLevelVcsManager" settingsEditedManually="false">
-    <OptionsSetting value="true" id="Add" />
-    <OptionsSetting value="true" id="Remove" />
-    <OptionsSetting value="true" id="Checkout" />
-    <OptionsSetting value="true" id="Update" />
-    <OptionsSetting value="true" id="Status" />
-    <OptionsSetting value="true" id="Edit" />
-    <ConfirmationsSetting value="0" id="Add" />
-    <ConfirmationsSetting value="0" id="Remove" />
-  </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_8" default="true" assert-keyword="true" jdk-15="true" project-jdk-name="1.8" project-jdk-type="JavaSDK">
-    <output url="file://$PROJECT_DIR$/out" />
-  </component>
-  <component name="masterDetails">
-    <states>
-      <state key="GlobalLibrariesConfigurable.UI">
-        <settings>
-          <splitter-proportions>
-            <option name="proportions">
-              <list>
-                <option value="0.2" />
-              </list>
-            </option>
-          </splitter-proportions>
-        </settings>
-      </state>
-      <state key="JdkListConfigurable.UI">
-        <settings>
-          <last-edited>1.8</last-edited>
-          <splitter-proportions>
-            <option name="proportions">
-              <list>
-                <option value="0.2" />
-              </list>
-            </option>
-          </splitter-proportions>
-        </settings>
-      </state>
-      <state key="ProjectJDKs.UI">
-        <settings>
-          <last-edited>1.8</last-edited>
-          <splitter-proportions>
-            <option name="proportions">
-              <list>
-                <option value="0.2" />
-              </list>
-            </option>
-          </splitter-proportions>
-        </settings>
-      </state>
-      <state key="ProjectLibrariesConfigurable.UI">
-        <settings>
-          <splitter-proportions>
-            <option name="proportions">
-              <list>
-                <option value="0.2" />
-              </list>
-            </option>
-          </splitter-proportions>
-        </settings>
-      </state>
-    </states>
-  </component>
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_6" assert-keyword="true" jdk-15="true" />
 </project>
\ No newline at end of file
diff --git a/unit5/.idea/modules.xml b/unit5/.idea/modules.xml
index bc277ce..6d963b6 100644
--- a/unit5/.idea/modules.xml
+++ b/unit5/.idea/modules.xml
@@ -1,8 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="ProjectModuleManager">
-    <modules>
-      <module fileurl="file://$PROJECT_DIR$/unit5.iml" filepath="$PROJECT_DIR$/unit5.iml" />
-    </modules>
+    <modules />
   </component>
 </project>
\ No newline at end of file
diff --git a/unit5/.idea/vcs.xml b/unit5/.idea/vcs.xml
index 6c0b863..6564d52 100644
--- a/unit5/.idea/vcs.xml
+++ b/unit5/.idea/vcs.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="VcsDirectoryMappings">
-    <mapping directory="$PROJECT_DIR$/.." vcs="Git" />
+    <mapping directory="" vcs="" />
   </component>
 </project>
\ No newline at end of file
diff --git a/unit5/.idea/workspace.xml b/unit5/.idea/workspace.xml
index 761af76..7a7fa61 100644
--- a/unit5/.idea/workspace.xml
+++ b/unit5/.idea/workspace.xml
@@ -23,38 +23,7 @@
     <favorites_list name="unit5" />
   </component>
   <component name="FileEditorManager">
-    <leaf>
-      <file leaf-file-name="Exercise3.java" pinned="false" current-in-tab="false">
-        <entry file="file://$PROJECT_DIR$/src/main/java/com/elephant/thinkinginjava/Exercise3.java">
-          <provider selected="true" editor-type-id="text-editor">
-            <state vertical-scroll-proportion="0.0">
-              <caret line="10" column="1" selection-start-line="6" selection-start-column="0" selection-end-line="10" selection-end-column="1" />
-              <folding>
-                <element signature="e#160#161#0" expanded="true" />
-                <element signature="e#239#240#0" expanded="true" />
-                <element signature="e#311#312#0" expanded="true" />
-                <element signature="e#389#390#0" expanded="true" />
-              </folding>
-            </state>
-          </provider>
-        </entry>
-      </file>
-      <file leaf-file-name="Exercise4.java" pinned="false" current-in-tab="true">
-        <entry file="file://$PROJECT_DIR$/src/main/java/com/elephant/thinkinginjava/Exercise4.java">
-          <provider selected="true" editor-type-id="text-editor">
-            <state vertical-scroll-proportion="0.4079498">
-              <caret line="13" column="1" selection-start-line="13" selection-start-column="1" selection-end-line="13" selection-end-column="1" />
-              <folding>
-                <element signature="e#137#138#0" expanded="true" />
-                <element signature="e#216#217#0" expanded="true" />
-                <element signature="e#251#252#0" expanded="true" />
-                <element signature="e#320#321#0" expanded="true" />
-              </folding>
-            </state>
-          </provider>
-        </entry>
-      </file>
-    </leaf>
+    <leaf />
   </component>
   <component name="FileTemplateManagerImpl">
     <option name="RECENT_TEMPLATES">
@@ -63,6 +32,9 @@
       </list>
     </option>
   </component>
+  <component name="Git.Settings">
+    <option name="RECENT_GIT_ROOT_PATH" value="$PROJECT_DIR$/.." />
+  </component>
   <component name="GradleLocalSettings">
     <option name="externalProjectsViewState">
       <projects_view />
@@ -80,6 +52,10 @@
         <option value="$PROJECT_DIR$/src/main/java/com/elephant/thinkinginjava/OverLoading.java" />
         <option value="$PROJECT_DIR$/src/main/java/com/elephant/thinkinginjava/Exercise3.java" />
         <option value="$PROJECT_DIR$/src/main/java/com/elephant/thinkinginjava/Exercise4.java" />
+        <option value="$PROJECT_DIR$/src/main/java/ArraryClassObj.java" />
+        <option value="$PROJECT_DIR$/src/main/java/com/elephant/thinkinginjava/ArraryClassObj.java" />
+        <option value="$PROJECT_DIR$/src/main/java/com/elephant/thinkinginjava/AynamicArray.java" />
+        <option value="$PROJECT_DIR$/src/main/java/com/elephant/thinkinginjava/Exercise16.java" />
       </list>
     </option>
   </component>
@@ -103,9 +79,8 @@
     <order />
   </component>
   <component name="ProjectFrameBounds">
-    <option name="y" value="23" />
     <option name="width" value="1440" />
-    <option name="height" value="823" />
+    <option name="height" value="900" />
   </component>
   <component name="ProjectLevelVcsManager" settingsEditedManually="false">
     <OptionsSetting value="true" id="Add" />
@@ -130,9 +105,8 @@
       <sortByType />
     </navigator>
     <panes>
-      <pane id="Scratches" />
-      <pane id="Scope" />
       <pane id="PackagesPane" />
+      <pane id="Scope" />
       <pane id="ProjectPane">
         <subPane>
           <PATH>
@@ -141,70 +115,9 @@
               <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.ProjectViewProjectNode" />
             </PATH_ELEMENT>
           </PATH>
-          <PATH>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="unit5" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.ProjectViewProjectNode" />
-            </PATH_ELEMENT>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="unit5" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.PsiDirectoryNode" />
-            </PATH_ELEMENT>
-          </PATH>
-          <PATH>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="unit5" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.ProjectViewProjectNode" />
-            </PATH_ELEMENT>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="unit5" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.PsiDirectoryNode" />
-            </PATH_ELEMENT>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="src" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.PsiDirectoryNode" />
-            </PATH_ELEMENT>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="test" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.PsiDirectoryNode" />
-            </PATH_ELEMENT>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="java" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.PsiDirectoryNode" />
-            </PATH_ELEMENT>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="thinkinginjava" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.PsiDirectoryNode" />
-            </PATH_ELEMENT>
-          </PATH>
-          <PATH>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="unit5" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.ProjectViewProjectNode" />
-            </PATH_ELEMENT>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="unit5" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.PsiDirectoryNode" />
-            </PATH_ELEMENT>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="src" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.PsiDirectoryNode" />
-            </PATH_ELEMENT>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="main" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.PsiDirectoryNode" />
-            </PATH_ELEMENT>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="java" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.PsiDirectoryNode" />
-            </PATH_ELEMENT>
-            <PATH_ELEMENT>
-              <option name="myItemId" value="thinkinginjava" />
-              <option name="myItemType" value="com.intellij.ide.projectView.impl.nodes.PsiDirectoryNode" />
-            </PATH_ELEMENT>
-          </PATH>
         </subPane>
       </pane>
+      <pane id="Scratches" />
     </panes>
   </component>
   <component name="PropertiesComponent">
@@ -217,16 +130,23 @@
     <property name="project.structure.side.proportion" value="0.0" />
     <property name="recentsLimit" value="5" />
     <property name="dynamic.classpath" value="false" />
+    <property name="FullScreen" value="true" />
+    <property name="last_opened_file_path" value="$USER_HOME$/Desktop" />
+  </component>
+  <component name="RecentsManager">
+    <key name="MoveClassesOrPackagesDialog.RECENTS_KEY">
+      <recent name="com.elephant.thinkinginjava" />
+    </key>
   </component>
-  <component name="RunManager" selected="Application.Exercise4">
-    <configuration default="false" name="Exercise1" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+  <component name="RunManager" selected="Application.Exercise16">
+    <configuration default="false" name="Exercise3" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
       <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea">
         <pattern>
           <option name="PATTERN" value="com.elephant.thinkinginjava.*" />
           <option name="ENABLED" value="true" />
         </pattern>
       </extension>
-      <option name="MAIN_CLASS_NAME" value="com.elephant.thinkinginjava.Exercise1" />
+      <option name="MAIN_CLASS_NAME" value="com.elephant.thinkinginjava.Exercise3" />
       <option name="VM_PARAMETERS" />
       <option name="PROGRAM_PARAMETERS" />
       <option name="WORKING_DIRECTORY" value="$PROJECT_DIR$" />
@@ -239,14 +159,14 @@
       <envs />
       <method />
     </configuration>
-    <configuration default="false" name="Exercise2" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+    <configuration default="false" name="Exercise4" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
       <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea">
         <pattern>
           <option name="PATTERN" value="com.elephant.thinkinginjava.*" />
           <option name="ENABLED" value="true" />
         </pattern>
       </extension>
-      <option name="MAIN_CLASS_NAME" value="com.elephant.thinkinginjava.Exercise2" />
+      <option name="MAIN_CLASS_NAME" value="com.elephant.thinkinginjava.Exercise4" />
       <option name="VM_PARAMETERS" />
       <option name="PROGRAM_PARAMETERS" />
       <option name="WORKING_DIRECTORY" value="$PROJECT_DIR$" />
@@ -259,14 +179,9 @@
       <envs />
       <method />
     </configuration>
-    <configuration default="false" name="OverLoading" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
-      <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea">
-        <pattern>
-          <option name="PATTERN" value="com.elephant.thinkinginjava.*" />
-          <option name="ENABLED" value="true" />
-        </pattern>
-      </extension>
-      <option name="MAIN_CLASS_NAME" value="com.elephant.thinkinginjava.OverLoading" />
+    <configuration default="false" name="ArraryClassObj" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+      <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
+      <option name="MAIN_CLASS_NAME" value="com.elephant.thinkinginjava.ArraryClassObj" />
       <option name="VM_PARAMETERS" />
       <option name="PROGRAM_PARAMETERS" />
       <option name="WORKING_DIRECTORY" value="$PROJECT_DIR$" />
@@ -279,14 +194,14 @@
       <envs />
       <method />
     </configuration>
-    <configuration default="false" name="Exercise3" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+    <configuration default="false" name="AynamicArray" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
       <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea">
         <pattern>
           <option name="PATTERN" value="com.elephant.thinkinginjava.*" />
           <option name="ENABLED" value="true" />
         </pattern>
       </extension>
-      <option name="MAIN_CLASS_NAME" value="com.elephant.thinkinginjava.Exercise3" />
+      <option name="MAIN_CLASS_NAME" value="com.elephant.thinkinginjava.AynamicArray" />
       <option name="VM_PARAMETERS" />
       <option name="PROGRAM_PARAMETERS" />
       <option name="WORKING_DIRECTORY" value="$PROJECT_DIR$" />
@@ -299,14 +214,14 @@
       <envs />
       <method />
     </configuration>
-    <configuration default="false" name="Exercise4" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
+    <configuration default="false" name="Exercise16" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
       <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea">
         <pattern>
           <option name="PATTERN" value="com.elephant.thinkinginjava.*" />
           <option name="ENABLED" value="true" />
         </pattern>
       </extension>
-      <option name="MAIN_CLASS_NAME" value="com.elephant.thinkinginjava.Exercise4" />
+      <option name="MAIN_CLASS_NAME" value="com.elephant.thinkinginjava.Exercise16" />
       <option name="VM_PARAMETERS" />
       <option name="PROGRAM_PARAMETERS" />
       <option name="WORKING_DIRECTORY" value="$PROJECT_DIR$" />
@@ -586,6 +501,12 @@
       <method />
     </configuration>
     <configuration default="true" type="js.build_tools.gulp" factoryName="Gulp.js">
+      <node-options />
+      <gulpfile />
+      <tasks />
+      <arguments />
+      <pass-parent-envs>true</pass-parent-envs>
+      <envs />
       <method />
     </configuration>
     <configuration default="true" type="osgi.bnd.run" factoryName="Run Launcher">
@@ -611,19 +532,19 @@
       <method />
     </configuration>
     <list size="5">
-      <item index="0" class="java.lang.String" itemvalue="Application.Exercise1" />
-      <item index="1" class="java.lang.String" itemvalue="Application.Exercise2" />
-      <item index="2" class="java.lang.String" itemvalue="Application.OverLoading" />
-      <item index="3" class="java.lang.String" itemvalue="Application.Exercise3" />
-      <item index="4" class="java.lang.String" itemvalue="Application.Exercise4" />
+      <item index="0" class="java.lang.String" itemvalue="Application.Exercise3" />
+      <item index="1" class="java.lang.String" itemvalue="Application.Exercise4" />
+      <item index="2" class="java.lang.String" itemvalue="Application.ArraryClassObj" />
+      <item index="3" class="java.lang.String" itemvalue="Application.AynamicArray" />
+      <item index="4" class="java.lang.String" itemvalue="Application.Exercise16" />
     </list>
     <recent_temporary>
       <list size="5">
-        <item index="0" class="java.lang.String" itemvalue="Application.Exercise4" />
-        <item index="1" class="java.lang.String" itemvalue="Application.Exercise3" />
-        <item index="2" class="java.lang.String" itemvalue="Application.OverLoading" />
-        <item index="3" class="java.lang.String" itemvalue="Application.Exercise2" />
-        <item index="4" class="java.lang.String" itemvalue="Application.Exercise1" />
+        <item index="0" class="java.lang.String" itemvalue="Application.Exercise16" />
+        <item index="1" class="java.lang.String" itemvalue="Application.AynamicArray" />
+        <item index="2" class="java.lang.String" itemvalue="Application.ArraryClassObj" />
+        <item index="3" class="java.lang.String" itemvalue="Application.Exercise4" />
+        <item index="4" class="java.lang.String" itemvalue="Application.Exercise3" />
       </list>
     </recent_temporary>
   </component>
@@ -633,6 +554,9 @@
     </option>
   </component>
   <component name="ShelveChangesManager" show_recycled="false" />
+  <component name="SvnConfiguration">
+    <configuration />
+  </component>
   <component name="TaskManager">
     <task active="true" id="Default" summary="Default task">
       <changelist id="f34f022f-7e4f-44b7-9ecd-0587dac4f0d2" name="Default" comment="" />
@@ -640,41 +564,45 @@
       <option name="number" value="Default" />
       <updated>1448196496784</updated>
       <workItem from="1448196499603" duration="2614000" />
+      <workItem from="1448775065914" duration="7000" />
+      <workItem from="1450076552488" duration="2432000" />
+      <workItem from="1450081516922" duration="546000" />
+      <workItem from="1450082969161" duration="64000" />
     </task>
     <servers />
   </component>
   <component name="TimeTrackingManager">
-    <option name="totallyTimeSpent" value="2614000" />
+    <option name="totallyTimeSpent" value="5663000" />
   </component>
   <component name="ToolWindowManager">
-    <frame x="0" y="23" width="1440" height="823" extended-state="6" />
-    <editor active="true" />
+    <frame x="0" y="0" width="1440" height="900" extended-state="6" />
+    <editor active="false" />
     <layout>
-      <window_info id="Palette&#9;" active="false" anchor="left" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" weight="0.33" sideWeight="0.5" order="-1" side_tool="false" content_ui="tabs" />
-      <window_info id="UI Designer" active="false" anchor="left" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" weight="0.33" sideWeight="0.5" order="-1" side_tool="false" content_ui="tabs" />
-      <window_info id="Designer" active="false" anchor="right" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" weight="0.33" sideWeight="0.5" order="-1" side_tool="false" content_ui="tabs" />
-      <window_info id="Palette" active="false" anchor="right" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" weight="0.33" sideWeight="0.5" order="-1" side_tool="false" content_ui="tabs" />
-      <window_info id="Terminal" active="false" anchor="bottom" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" weight="0.33" sideWeight="0.5" order="-1" side_tool="false" content_ui="tabs" />
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@@ -688,107 +616,6 @@
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diff --git a/unit5/pom.xml b/unit5/pom.xml
deleted file mode 100644
index 9f9bc51..0000000
--- a/unit5/pom.xml
+++ /dev/null
@@ -1,25 +0,0 @@
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-  <modelVersion>4.0.0</modelVersion>
-
-  <groupId>com.elephant.thinkinginjava</groupId>
-  <artifactId>unit5</artifactId>
-  <version>1.0</version>
-  <packaging>jar</packaging>
-
-  <name>unit5</name>
-  <url>http://maven.apache.org</url>
-
-  <properties>
-    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-  </properties>
-
-  <dependencies>
-    <dependency>
-      <groupId>junit</groupId>
-      <artifactId>junit</artifactId>
-      <version>3.8.1</version>
-      <scope>test</scope>
-    </dependency>
-  </dependencies>
-</project>
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/BananaPeel.java b/unit5/src/main/java/com/elephant/thinkinginjava/BananaPeel.java
deleted file mode 100644
index dca715a..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/BananaPeel.java
+++ /dev/null
@@ -1,19 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- * Key word : this
- */
-
-class Banana{
-    void peel(int i){
-        System.out.println("I am peel,this object number is : "+i);
-    }
-}
-public class BananaPeel {
-    public static void main(String[] args){
-        Banana b1=new Banana(),b2=new Banana();
-        b1.peel(1);
-        b2.peel(2);
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise1.java b/unit5/src/main/java/com/elephant/thinkinginjava/Exercise1.java
deleted file mode 100644
index 0354d95..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise1.java
+++ /dev/null
@@ -1,19 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- */
-
-class InitialStringIsNull{
-    String s;
-    void p(){
-        System.out.println("Initial String is:"+s+".");
-    }
-}
-
-public class Exercise1 {
-    public static void main(String[] args){
-        InitialStringIsNull Is=new InitialStringIsNull();
-        Is.p();
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise10.java b/unit5/src/main/java/com/elephant/thinkinginjava/Exercise10.java
deleted file mode 100644
index 291d2e7..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise10.java
+++ /dev/null
@@ -1,33 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/28.
- */
-class QQ{
-    boolean status; //initialize is false.
-    QQ(boolean s){
-        status=s;
-    }
-    void Login(){
-        status=true;
-    }
-    void Logout(){
-        status=false;
-    }
-    protected void finalize(){
-     if(status)
-         System.out.println("Some counts still login!");
-    }
-}
-
-public class Exercise10 {
-    public static void main(String[] args){
-        QQ mycount=new QQ(true);
-        QQ yours=new QQ(false);
-        QQ his=new QQ(true);
-        mycount.Logout();
-        yours.Login();
-        his.Login();
-        System.gc();
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise11.java b/unit5/src/main/java/com/elephant/thinkinginjava/Exercise11.java
deleted file mode 100644
index a40f20a..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise11.java
+++ /dev/null
@@ -1,18 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/28.
- */
-
-public class Exercise11 {
-    public static void main(String[] args){
-        QQ mycount=new QQ(true);
-        QQ yours=new QQ(false);
-        QQ his=new QQ(true);
-        mycount.Logout();
-        yours.Login();
-        his.Login();
-        System.gc();
-        System.runFinalization();
-    }
-}
\ No newline at end of file
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise2.java b/unit5/src/main/java/com/elephant/thinkinginjava/Exercise2.java
deleted file mode 100644
index e5c97a5..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise2.java
+++ /dev/null
@@ -1,20 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- */
-class InitialAndConstructor{
-    String s1="Definition";
-    String s2;
-    InitialAndConstructor(String s){
-        s2=s;
-    }
-}
-
-public class Exercise2 {
-    public static void main(String[] args){
-        InitialAndConstructor ic=new InitialAndConstructor("Constructor");
-        System.out.println(ic.s1);
-        System.out.println(ic.s2);
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise3.java b/unit5/src/main/java/com/elephant/thinkinginjava/Exercise3.java
deleted file mode 100644
index 266d6a6..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise3.java
+++ /dev/null
@@ -1,17 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- * Test default constructor
- */
-class DefautlConstructor{
-    DefautlConstructor(){
-        System.out.println("DefaultConstructor initialize the object!");
-    }
-}
-
-public class Exercise3 {
-    public static void main(String[] args){
-        DefautlConstructor defautlConstructor=new DefautlConstructor();
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise4.java b/unit5/src/main/java/com/elephant/thinkinginjava/Exercise4.java
deleted file mode 100644
index 4a6a0ec..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise4.java
+++ /dev/null
@@ -1,20 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- *
- */
-class DefautlConstructor2{
-    DefautlConstructor2(){
-        System.out.println("DefaultConstructor initialize the object!");
-    }
-    DefautlConstructor2(String s){
-        System.out.println(s+"Constructor with parameter:"+s);
-    }
-}
-public class Exercise4 {
-    public static void main(String[] args){
-        DefautlConstructor2 dc1=new DefautlConstructor2();
-        DefautlConstructor2 dc2=new DefautlConstructor2("I am the paramter!");
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise5.java b/unit5/src/main/java/com/elephant/thinkinginjava/Exercise5.java
deleted file mode 100644
index 41ef245..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise5.java
+++ /dev/null
@@ -1,20 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- */
-class Dog{
-    void bark(){
-        System.out.println("barking!");
-    }
-    void bark(String s){
-        System.out.println("howling");
-    }
-}
-public class Exercise5 {
-    public static void main(String[] args){
-        Dog dog=new Dog();
-        dog.bark();
-        dog.bark("howling");
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise6.java b/unit5/src/main/java/com/elephant/thinkinginjava/Exercise6.java
deleted file mode 100644
index d6f3048..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise6.java
+++ /dev/null
@@ -1,23 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- * Test if different paramter order can overloading
- */
-class Dog1{
-    void bark(int i,String s){
-        System.out.print("Int first,String second.");
-        System.out.println("barking!");
-    }
-    void bark(String s,int i){
-        System.out.print("String first,Int second.");
-        System.out.println("howling");
-    }
-}
-public class Exercise6 {
-    public static void main(String[] args){
-        Dog1 dog1=new Dog1();
-        dog1.bark(1,"2");
-        dog1.bark("1",2);
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise7.java b/unit5/src/main/java/com/elephant/thinkinginjava/Exercise7.java
deleted file mode 100644
index a8d4a43..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise7.java
+++ /dev/null
@@ -1,15 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- */
-
-class WithDefaultConstructor{
-
-}
-public class Exercise7 {
-    public static void main(String[] args){
-        WithDefaultConstructor w=new WithDefaultConstructor();
-
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise8.java b/unit5/src/main/java/com/elephant/thinkinginjava/Exercise8.java
deleted file mode 100644
index dc70b4e..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise8.java
+++ /dev/null
@@ -1,20 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- * Verify if we must use this in same class different function
- */
-public class Exercise8 {
-    void first(){
-        System.out.println("I am the first function.");
-        second();
-        this.second();
-    }
-    void second(){
-        System.out.println("I am the second function.");
-    }
-    public static void main(String[] args){
-    Exercise8 exercise8=new Exercise8();
-        exercise8.first();
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise9.java b/unit5/src/main/java/com/elephant/thinkinginjava/Exercise9.java
deleted file mode 100644
index 0d50abb..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Exercise9.java
+++ /dev/null
@@ -1,17 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- */
-public class Exercise9 {
-    Exercise9(){
-        System.out.println("Constructor with no paramter,in the first one.");
-    }
-    Exercise9(String s){
-        this();
-        System.out.println("Constructor with String s,in the second one.");
-    }
-    public static void main(String[] args){
-        new Exercise9("s");
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Flower.java b/unit5/src/main/java/com/elephant/thinkinginjava/Flower.java
deleted file mode 100644
index 5548995..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Flower.java
+++ /dev/null
@@ -1,35 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- */
-public class Flower {
-    int petalCount=0;
-    String s="initial value";
-    Flower(int petals){
-        petalCount=petals;
-        System.out.println("Constructor with int petals,petalCount="+petalCount);
-    }
-    Flower(String ss){
-        s=ss;
-        System.out.println("Constructor with String ss,s="+s);
-    }
-    Flower(String ss,int petals){
-        this(ss);
-     //this(petals);//this可以调用构造函数，但是不能同时调用两个
-        this.petalCount=petals;
-        System.out.println("Constructor with String ss and int petals,");
-    }
-    Flower(){
-        this("hi",7);
-        System.out.println("Constructor with no paramters");
-    }
-    void printPetalCount(){
-       // this(22);//this 只能在构造函数中使用this，调用其他构造函数。
-        System.out.println("peltalsCount="+petalCount+",s="+s);
-    }
-    public static void main(String[] args){
-        Flower flower=new Flower();
-        flower.printPetalCount();
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/Leaf.java b/unit5/src/main/java/com/elephant/thinkinginjava/Leaf.java
deleted file mode 100644
index 390785e..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/Leaf.java
+++ /dev/null
@@ -1,21 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- * return this
- */
-public class Leaf {
-    int i=0;
-    Leaf incrment(){
-        i++;
-        return this;
-    }
-    void p(){
-        System.out.println("i="+i);
-    }
-    public static void main(String[] args){
-        Leaf leaf=new Leaf();
-        leaf.incrment().incrment().incrment();
-        leaf.p();
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/OverLoading.java b/unit5/src/main/java/com/elephant/thinkinginjava/OverLoading.java
deleted file mode 100644
index 511ba98..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/OverLoading.java
+++ /dev/null
@@ -1,36 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- * Test function overloading
- */
-
-class Tree{
-    int height;
-    Tree(){
-        System.out.println("我是小树苗，高度为0");
-        height=0;
-    }
-    Tree(int i){
-        System.out.println("我已经长高了，我的高度为：" +i);
-        height=i;
-    }
-    void info(){
-        System.out.println("我的高度是："+height);
-    }
-    void info(String s){
-        System.out.println(s+":我的告诉是"+height);
-    }
-}
-
-
-public class OverLoading {
-    public static void main(String[] args) {
-         Tree tree1=new Tree();
-         Tree tree2=new Tree(7);
-         tree1.info();
-         tree1.info("OverLoading info");
-         tree2.info();
-         tree2.info("OverLoading info");
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/PassingThis.java b/unit5/src/main/java/com/elephant/thinkinginjava/PassingThis.java
deleted file mode 100644
index 21ba226..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/PassingThis.java
+++ /dev/null
@@ -1,29 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- * Pass this object among class
- */
-class Person{
-   public void eat(Apple apple){
-       Apple peeled=apple.getpeeled();
-       System.out.println("Yummy!");
-   }
-}
-class Peeler{
-    static Apple peel(Apple apple){
-        return apple;
-    }
-}
-class Apple{
-    Apple getpeeled(){
-        return Peeler.peel(this);
-    }
-}
-
-public class PassingThis {
-    public static void main(String[] args){
-        new Person().eat(new Apple());
-    }
-
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/SimpleConstructor.java b/unit5/src/main/java/com/elephant/thinkinginjava/SimpleConstructor.java
deleted file mode 100644
index 6eb1fce..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/SimpleConstructor.java
+++ /dev/null
@@ -1,18 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Hello world!
- *
- */
-class Rock{
-    Rock(){
-        System.out.println("Rock");
-    }
-}
-public class  SimpleConstructor{
-    public static void main(String[] args){
-        for(int i=0;i<10;i++)
-            new Rock();
-    }
-
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/SimpleConstructor2.java b/unit5/src/main/java/com/elephant/thinkinginjava/SimpleConstructor2.java
deleted file mode 100644
index eebd680..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/SimpleConstructor2.java
+++ /dev/null
@@ -1,22 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/22.
- */
-
-/**
- * Constructot with param
- */
-
-class Rock2{
-    Rock2(int i){
-        System.out.println("Rock" + i + ",");
-    }
-}
-public class SimpleConstructor2 {
-    public static void main(String[] args){
-        for(int i=0;i<10;i++){
-            new Rock2(i);
-        }
-    }
-}
diff --git a/unit5/src/main/java/com/elephant/thinkinginjava/TerminationCondition.java b/unit5/src/main/java/com/elephant/thinkinginjava/TerminationCondition.java
deleted file mode 100644
index 68fee29..0000000
--- a/unit5/src/main/java/com/elephant/thinkinginjava/TerminationCondition.java
+++ /dev/null
@@ -1,28 +0,0 @@
-package com.elephant.thinkinginjava;
-
-/**
- * Created by elephant on 15/11/28.
- */
-
-class Book{
-    boolean checkedOut=false;
-    Book(boolean checkOut){
-        checkedOut=checkOut;
-    }
-    void checkedIn(){
-        checkedOut=false;
-    }
-    protected void finalize(){
-        if(checkedOut)
-            System.out.println("ERROR:checked out!");
-    }
-}
-
-public class TerminationCondition {
-    public static void main(String[] args){
-        Book novel=new Book(true);
-        novel.checkedIn();
-        new Book(true);
-        System.gc();
-    }
-}
diff --git a/unit5/src/test/java/com/elephant/thinkinginjava/RockTest.java b/unit5/src/test/java/com/elephant/thinkinginjava/RockTest.java
deleted file mode 100644
index f3ccdbc..0000000
--- a/unit5/src/test/java/com/elephant/thinkinginjava/RockTest.java
+++ /dev/null
@@ -1,38 +0,0 @@
-package com.elephant.thinkinginjava;
-
-import junit.framework.Test;
-import junit.framework.TestCase;
-import junit.framework.TestSuite;
-
-/**
- * Unit test for simple Rock.
- */
-public class RockTest
-    extends TestCase
-{
-    /**
-     * Create the test case
-     *
-     * @param testName name of the test case
-     */
-    public RockTest(String testName)
-    {
-        super( testName );
-    }
-
-    /**
-     * @return the suite of tests being tested
-     */
-    public static Test suite()
-    {
-        return new TestSuite( RockTest.class );
-    }
-
-    /**
-     * Rigourous Test :-)
-     */
-    public void testApp()
-    {
-        assertTrue( true );
-    }
-}
diff --git a/unit5/target/classes/com/elephant/thinkinginjava/DefautlConstructor.class b/unit5/target/classes/com/elephant/thinkinginjava/DefautlConstructor.class
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index e6e8034..0000000
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diff --git a/unit5/target/classes/com/elephant/thinkinginjava/Exercise1.class b/unit5/target/classes/com/elephant/thinkinginjava/Exercise1.class
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diff --git a/unit5/target/classes/com/elephant/thinkinginjava/Exercise4.class b/unit5/target/classes/com/elephant/thinkinginjava/Exercise4.class
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diff --git a/unit5/target/classes/com/elephant/thinkinginjava/InitialAndConstructor.class b/unit5/target/classes/com/elephant/thinkinginjava/InitialAndConstructor.class
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diff --git a/unit5/target/classes/com/elephant/thinkinginjava/InitialStringIsNull.class b/unit5/target/classes/com/elephant/thinkinginjava/InitialStringIsNull.class
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index 14e6bfa..0000000
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diff --git a/unit5/target/classes/com/elephant/thinkinginjava/OverLoading.class b/unit5/target/classes/com/elephant/thinkinginjava/OverLoading.class
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diff --git a/unit5/target/classes/com/elephant/thinkinginjava/Rock.class b/unit5/target/classes/com/elephant/thinkinginjava/Rock.class
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diff --git a/unit5/target/classes/com/elephant/thinkinginjava/Tree.class b/unit5/target/classes/com/elephant/thinkinginjava/Tree.class
deleted file mode 100644
index 4a479f0..0000000
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diff --git a/unit5/target/test-classes/com/elephant/thinkinginjava/RockTest.class b/unit5/target/test-classes/com/elephant/thinkinginjava/RockTest.class
deleted file mode 100644
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diff --git a/unit5/unit5.iml b/unit5/unit5.iml
deleted file mode 100644
index b1562b6..0000000
--- a/unit5/unit5.iml
+++ /dev/null
@@ -1,15 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<module org.jetbrains.idea.maven.project.MavenProjectsManager.isMavenModule="true" type="JAVA_MODULE" version="4">
-  <component name="NewModuleRootManager" LANGUAGE_LEVEL="JDK_1_5" inherit-compiler-output="false">
-    <output url="file://$MODULE_DIR$/target/classes" />
-    <output-test url="file://$MODULE_DIR$/target/test-classes" />
-    <content url="file://$MODULE_DIR$">
-      <sourceFolder url="file://$MODULE_DIR$/src/main/java" isTestSource="false" />
-      <sourceFolder url="file://$MODULE_DIR$/src/test/java" isTestSource="true" />
-      <excludeFolder url="file://$MODULE_DIR$/target" />
-    </content>
-    <orderEntry type="inheritedJdk" />
-    <orderEntry type="sourceFolder" forTests="false" />
-    <orderEntry type="library" scope="TEST" name="Maven: junit:junit:3.8.1" level="project" />
-  </component>
-</module>
\ No newline at end of file
