diff --git a/.obsidian/workspace.json b/.obsidian/workspace.json
index 43e246d..ed27723 100644
--- a/.obsidian/workspace.json
+++ b/.obsidian/workspace.json
@@ -21,7 +21,7 @@
             "state": {
               "type": "markdown",
               "state": {
-                "file": "Data Structures/Week 5/Untitled.md",
+                "file": "Data Structures/Week 5/Lecture 9 - Stacks.md",
                 "mode": "source",
                 "source": false
               }
@@ -95,7 +95,7 @@
             "state": {
               "type": "backlink",
               "state": {
-                "file": "Data Structures/Week 5/Untitled.md",
+                "file": "Data Structures/Week 5/Lecture 9 - Stacks.md",
                 "collapseAll": false,
                 "extraContext": false,
                 "sortOrder": "alphabetical",
@@ -112,7 +112,7 @@
             "state": {
               "type": "outgoing-link",
               "state": {
-                "file": "Data Structures/Week 5/Untitled.md",
+                "file": "Data Structures/Week 5/Lecture 9 - Stacks.md",
                 "linksCollapsed": false,
                 "unlinkedCollapsed": true
               }
@@ -135,7 +135,7 @@
             "state": {
               "type": "outline",
               "state": {
-                "file": "Data Structures/Week 5/Untitled.md"
+                "file": "Data Structures/Week 5/Lecture 9 - Stacks.md"
               }
             }
           },
@@ -185,10 +185,10 @@
       "mermaid-tools:Open Mermaid Toolbar": false
     }
   },
-  "active": "3ed058b7ba32ddc0",
+  "active": "ff4e63a36b080692",
   "lastOpenFiles": [
     "Software Project with Agile Techinques/Week 3/Study Skills - Class Diagrams.md",
-    "Data Structures/Week 5/Untitled.md",
+    "Data Structures/Week 5/Lecture 9 - Stacks.md",
     "Data Structures/Week 5",
     "README.md",
     "AI & Data Mining/Week 4/Tutorial 4 - Nearest Neighbor.md",
diff --git a/Data Structures/Week 5/Lecture 9 - Stacks.md b/Data Structures/Week 5/Lecture 9 - Stacks.md
index e69de29..f03f694 100644
--- a/Data Structures/Week 5/Lecture 9 - Stacks.md	
+++ b/Data Structures/Week 5/Lecture 9 - Stacks.md	
@@ -0,0 +1 @@
+dd