diff --git a/.idea/.gitignore b/.idea/.gitignore
new file mode 100644
index 0000000000000000000000000000000000000000..26d33521af10bcc7fd8cea344038eaaeb78d0ef5
--- /dev/null
+++ b/.idea/.gitignore
@@ -0,0 +1,3 @@
+# Default ignored files
+/shelf/
+/workspace.xml
diff --git a/.idea/codeStyles/Project.xml b/.idea/codeStyles/Project.xml
new file mode 100644
index 0000000000000000000000000000000000000000..919ce1f1f77253454105acb2aad9997c1047a0e6
--- /dev/null
+++ b/.idea/codeStyles/Project.xml
@@ -0,0 +1,7 @@
+<component name="ProjectCodeStyleConfiguration">
+  <code_scheme name="Project" version="173">
+    <ScalaCodeStyleSettings>
+      <option name="MULTILINE_STRING_CLOSING_QUOTES_ON_NEW_LINE" value="true" />
+    </ScalaCodeStyleSettings>
+  </code_scheme>
+</component>
\ No newline at end of file
diff --git a/.idea/codeStyles/codeStyleConfig.xml b/.idea/codeStyles/codeStyleConfig.xml
new file mode 100644
index 0000000000000000000000000000000000000000..a55e7a179bde3e4e772c29c0c85e53354aa54618
--- /dev/null
+++ b/.idea/codeStyles/codeStyleConfig.xml
@@ -0,0 +1,5 @@
+<component name="ProjectCodeStyleConfiguration">
+  <state>
+    <option name="PREFERRED_PROJECT_CODE_STYLE" value="Default" />
+  </state>
+</component>
\ No newline at end of file
diff --git a/.idea/lec09-graph.iml b/.idea/lec09-graph.iml
new file mode 100644
index 0000000000000000000000000000000000000000..d6ebd4805981b8400db3e3291c74a743fef9a824
--- /dev/null
+++ b/.idea/lec09-graph.iml
@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$" />
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
new file mode 100644
index 0000000000000000000000000000000000000000..40674af8d699c0ff4e92f9e8639ff4904ce4bdea
--- /dev/null
+++ b/.idea/misc.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_15" project-jdk-name="15" project-jdk-type="JavaSDK">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/modules.xml b/.idea/modules.xml
new file mode 100644
index 0000000000000000000000000000000000000000..439f2c376b74496b5c46787cd118684bddf971ce
--- /dev/null
+++ b/.idea/modules.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/lec09-graph.iml" filepath="$PROJECT_DIR$/.idea/lec09-graph.iml" />
+    </modules>
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 0000000000000000000000000000000000000000..35eb1ddfbbc029bcab630581847471d7f238ec53
--- /dev/null
+++ b/.idea/vcs.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/Homework/Homework.java b/Homework/Homework.java
new file mode 100644
index 0000000000000000000000000000000000000000..7d11ef5d0d9510cf8e1ef090243cc82c53526f2e
--- /dev/null
+++ b/Homework/Homework.java
@@ -0,0 +1,146 @@
+public class Homework {
+    private char[] mVexs;
+    private int[][] mMatrix;
+    public T(char[] vexs, char[][] edges){
+        int vlen=vexs.length;
+        int elen=edges.length;
+        mVexs=new char[vlen];
+        for(int i=0;i<vlen;i++){
+            mVexs[i]=vexs[i];
+        }
+        mMatrix=new int[vlen][vlen];
+        for(int i=0;i<elen;i++){
+
+            int pos1=getPos(edges[i][0]);
+            int pos2=getPos(edges[i][1]);
+            mMatrix[pos1][pos2]=1;
+        }
+    }
+    private int getPos(char c) {
+
+        for(int i=0;i<mVexs.length;i++){
+            if(mVexs[i]==c){
+                return i;
+            }
+        }return -1;
+    }
+
+    private int nextVertex(int i, int w) {
+        for(int j=w+1;j<mVexs.length;j++){
+            if(mMatrix[i][j]==1){
+                return j;
+            }
+        }return -1;
+
+    }
+
+    private int firstVertex(int i) {
+
+        for(int j=0;j<mVexs.length;j++){
+            if(mMatrix[i][j]==1){
+                return j;
+            }
+        }return -1;
+    }
+
+    public void print(){
+        for(int i=0;i<mMatrix.length;i++){
+            for(int j=0;j<mMatrix[i].length;j++){
+                System.out.print(mMatrix[i][j]+" ");
+            }
+            System.out.println();
+        }
+    }
+    public static void main(String[] args) {
+
+        char[] vexs = {'A', 'B', 'C', 'D','E','F','G','H','I'};
+        char[][] edges = new char[][]{
+                {'A', 'B'},
+                {'A', 'F'},
+                {'B', 'G'},
+                {'B', 'C'},
+                {'B', 'I'},
+                {'C', 'B'},
+                {'C', 'I'},
+                {'C', 'D'},
+                {'D', 'C'},
+                {'D', 'I'},
+                {'D', 'G'},
+                {'D', 'H'},
+                {'D', 'E'},
+                {'E', 'H'},
+                {'E', 'F'},
+                {'F', 'G'},
+                {'F', 'A'},
+                {'F', 'E'},
+                {'G', 'H'},
+                {'G', 'D'},
+                {'G', 'B'},
+                {'H', 'G'},
+                {'H', 'D'},
+                {'H', 'E'},
+                {'I', 'B'},
+                {'I', 'C'}
+
+        };
+        T pG;
+        pG = new T(vexs, edges);
+        pG.print();
+        pG.DFS();
+        pG.BFS();
+    }
+    private void BFS() {
+        int head=0;
+        int rear=0;
+        int[] queue=new int[this.mVexs.length];
+        boolean[] visited=new boolean[this.mVexs.length];
+        for (int i = 0; i < mVexs.length; i++){
+            visited[i] = false;
+        }
+        System.out.println("BFS:");
+        for(int i=0;i<mVexs.length;i++){
+            if(visited[i]==false){
+                visited[i]=true;
+                System.out.print(" "+mVexs[i]);
+                queue[rear++]=i;
+            }
+            while(head!=rear){
+                int j=queue[head++];
+                int k=firstVertex(j);
+                while(k>=0){
+                    if(visited[k]==false){
+                        visited[k]=true;
+                        System.out.print(" "+mVexs[k]);
+                        queue[rear++]=k;
+                    }
+                    k=nextVertex(j,k);
+                }
+            }
+        }
+
+
+    }
+    private void DFS() {
+        boolean[] visited=new boolean[mVexs.length];
+        System.out.println("DFS:");
+        for(int i=0;i<mVexs.length;i++){
+            if(visited[i]==false){
+                DFS(i,visited);
+            }
+        }
+        System.out.println();
+
+    }
+    private void DFS(int i, boolean[] visited) {
+        visited[i]=true;
+        System.out.print(" "+mVexs[i]);
+        int w=firstVertex(i);//i:A,w:B
+        while(w>=0){
+            if(visited[w]==false){
+                DFS(w,visited);
+            }
+            w=nextVertex(i,w);
+        }
+        i--;
+    }
+}
diff --git a/README.md b/README.md
index c7dc5aa5bba1afbc05a618946e230510e5bfd2c2..7c746b86f53960d3119d671558e6b29633ff82a6 100644
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@
 
 ### 截止日期
 
-2021.1.6
+2021.1.13
 
 ### 基础