diff --git a/.obsidian/workspace.json b/.obsidian/workspace.json
index 3e52276..1df8967 100644
--- a/.obsidian/workspace.json
+++ b/.obsidian/workspace.json
@@ -4,25 +4,11 @@
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-              "title": "2b - Round Robin algorithm"
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@@ -35,29 +21,6 @@
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@@ -115,8 +78,7 @@
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+    "width": 307.5
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@@ -231,13 +193,13 @@
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-    "Concurrent Systems/notes/2b - Round Robin algorithm.md",
-    "Concurrent Systems/notes/1 - CS Basics.md",
     "Concurrent Systems/notes/2 - Fast mutex by Lamport.md",
+    "Concurrent Systems/notes/1 - CS Basics.md",
+    "Concurrent Systems/notes/2b - Round Robin algorithm.md",
+    "Concurrent Systems/notes/3.md",
     "Concurrent Systems/notes/1b - Peterson algorithm.md",
     "HCIW/slides/Interface and Interaction for IoT.pdf",
     "Pasted image 20250305182542.png",
diff --git a/Concurrent Systems/notes/3.md b/Concurrent Systems/notes/3.md
index 3802f7e..45fb2dd 100644
--- a/Concurrent Systems/notes/3.md	
+++ b/Concurrent Systems/notes/3.md	
@@ -91,3 +91,19 @@ X.fetch&add(v) :=
 	return tmp
 ```
 
+###### How do we use it for MUTEX?
+```
+Initialize TICKET and NEXT at 0
+
+lock() :=
+	my_ticket <- TICKET.fetch&add(1)
+	wait my_ticket = NEXT
+	return
+
+unlock() :=
+	NEXT <- NEXT + 1
+	return
+```
+
+>[!info} It is bounded bypass with bound n-1
+