diff --git a/.obsidian/workspace.json b/.obsidian/workspace.json
index 295b6ff..a786ebb 100644
--- a/.obsidian/workspace.json
+++ b/.obsidian/workspace.json
@@ -40,18 +40,18 @@
             "id": "add960c244d7897d",
             "type": "leaf",
             "state": {
-              "type": "webviewer",
+              "type": "markdown",
               "state": {
-                "url": "https://share.note.youdao.com/ynoteshare/index.html?id=a66c778ce8c6e4ee03608e493e59ba7a&type=notebook&_time=1768473840238#/WEB5c35414ed043f2b383d52a7ee225b9ac",
-                "title": "CQ2605",
-                "mode": "webview"
+                "file": "YueQian/Homework/2-4.md",
+                "mode": "source",
+                "source": false,
+                "backlinks": false
               },
-              "icon": "globe-2",
-              "title": "CQ2605"
+              "icon": "lucide-file",
+              "title": "2-4"
             }
           }
-        ],
-        "currentTab": 2
+        ]
       }
     ],
     "direction": "vertical"
@@ -118,12 +118,13 @@
             "state": {
               "type": "outline",
               "state": {
+                "file": "YueQian/相关网站.md",
                 "followCursor": true,
                 "showSearch": false,
                 "searchQuery": ""
               },
               "icon": "lucide-list",
-              "title": "大纲"
+              "title": "相关网站 的大纲"
             }
           },
           {
@@ -233,7 +234,7 @@
             }
           }
         ],
-        "currentTab": 2
+        "currentTab": 3
       },
       {
         "id": "bf1e7d1a52b4651c",
@@ -274,8 +275,9 @@
       "remotely-save:Remotely Save": false
     }
   },
-  "active": "add960c244d7897d",
+  "active": "e0e88d3f2dd6fbc1",
   "lastOpenFiles": [
+    "YueQian/Homework/2-4.md",
     "YueQian/相关网站.md",
     "Diary/2026-2/2026-2-4 周三.md",
     "YueQian/Homework/~WRL0001.tmp",
@@ -314,7 +316,6 @@
     "Excalidraw/Drawing 20260122.md",
     "Diary/2026-1/2026-1-27 周二.md",
     "Diary/2026-1/2026-1-26 周一.md",
-    "Diary/2026-1/2026-1-25 周日.md",
     "Excalidraw/Untitled.canvas",
     "Article/Studyroad/vivado_ip_img/IPCore10.png",
     "Article/Studyroad/vivado_ip_img/IPCore07.png",
diff --git a/YueQian/Homework/2-4.md b/YueQian/Homework/2-4.md
new file mode 100644
index 0000000..d125f98
--- /dev/null
+++ b/YueQian/Homework/2-4.md
@@ -0,0 +1,107 @@
+---
+tags:
+  - empty
+aliases: empty
+日期: 2026/2/4
+---
+```c
+
+#include <stdio.h>
+
+void bubble_sort(int *arr,int len)
+{
+    for(int i=0;i<len;i++){
+        for(int j=0;j<len-i-1;j++){
+            if(arr[j] > arr[j+1]){
+                arr[j] ^= arr[j+1];
+                arr[j+1] ^= arr[j];
+                arr[j] ^= arr[j+1];
+            }
+        }
+    }
+}
+
+  
+
+void insertion_sort(int *arr,int len)
+{
+    int point=0,temp=0;
+    for(int i=1;i<len;i++){
+        if(arr[i+1] < arr[i]){
+            point = i+1;
+            for(int j=point;j>0;j--){
+                if(arr[j-1] > arr[j]){
+                    temp = arr[j-1];
+                    arr[j-1] = arr[j];
+                    arr[j] = temp;
+                }
+            }
+        }
+    }
+}
+
+void selection_sort(int *arr, int len)
+{
+    int min_val,min_index,temp = 0;
+    for (int i = 0; i < len - 1; i++){
+        min_index = i;
+        min_val = arr[i];
+        for (int j = i + 1; j < len; j++){
+            if (arr[j] < min_val){
+                min_val = arr[j];
+                min_index = j;
+            }
+        }
+        temp = arr[i];
+        arr[i] = min_val;
+        arr[min_index] = temp;
+    }
+}
+
+  
+
+void quick_sort(int *arr, int left, int right)
+{
+    if (left > right)
+        return;
+
+    int tmp = arr[left];
+    int i = left;
+    int j = right;
+  
+    while (i != j){
+        while (arr[j] >= tmp && j > i)
+            j--;
+        while (arr[i] <= tmp && j > i)
+            i++;
+
+        if (j > i){
+            int t = arr[i];
+            arr[i] = arr[j];
+            arr[j] = t;
+        }
+    }
+    arr[left] = arr[i];
+    arr[i] = tmp;
+
+    quick_sort(arr, left, i - 1);
+    quick_sort(arr, i + 1, right);
+}
+
+void shell_sort(int *arr, int len)
+{
+
+}
+
+int main(int argc, char const *argv[])
+{
+    int arr[20] = {3,44,28,5,47,36,27,26,89,58,11,31,14,51,54,67,76,68,89,45};
+    int len = sizeof(arr)/sizeof(arr[0]);
+    //quick_sort(arr,0,len-1);
+
+    for(int i=0;i<len;i++)
+        printf("%d ",arr[i]);
+    printf("\n");
+    return 0;
+}
+```
\ No newline at end of file