Disallow search crawling

build.py

@@ -75,6 +75,22 @@ def scan_shared() -> list[Section]:
 
     assignments_dir = SHARED_DIR / "assignments"
     if assignments_dir.exists():
+        subdirs = sorted(
+            d for d in assignments_dir.iterdir()
+            if d.is_dir() and should_include(d)
+        )
+        if subdirs:
+            subsections = []
+            for subdir in subdirs:
+                zip_name = f"assignments-{subdir.name}.zip"
+                create_zip(subdir, ZIPS_DIR / zip_name)
+                subsections.append(SubSection(
+                    name=subdir.name,
+                    zip_url=f"zips/{zip_name}",
+                    files=list_files(subdir),
+                ))
+            sections.append(Section(title="Assignments", subsections=subsections))
+        else:
             zip_name = "assignments.zip"
             create_zip(assignments_dir, ZIPS_DIR / zip_name)
             sections.append(Section(
@@ -258,6 +274,10 @@ def main() -> None:
     output.write_text(html_content, encoding="utf-8")
     print(f"Built {output}")
 
+    robots = PUBLIC_DIR / "robots.txt"
+    robots.write_text("User-agent: *\nDisallow: /\n", encoding="utf-8")
+    print(f"Built {robots}")
+
     print(f"Zips in {ZIPS_DIR}:")
     for z in sorted(ZIPS_DIR.iterdir()):
         print(f"  {z.name}")

shared/notes-and-examples/2026.02.28/homework.py

@@ -0,0 +1,2 @@
+# Homework:
+# See youtube-playlists under Assignments

shared/notes-and-examples/2026.02.28/queues.py

@@ -0,0 +1,51 @@
+class Node:
+    next_node: "None | Node" = None
+    prev_node: "None | Node" = None
+
+    def __init__(self, value):
+        self.value = value
+
+class Queue:
+    front: "Node | None" = None
+    back: "Node | None" = None
+
+    def append(self, value):
+        if self.back is None:
+            self.front = Node(value)
+            self.back = self.front
+        else:
+            new_node = Node(value)
+            self.back.prev_node = new_node
+            new_node.next_node = self.back
+            self.back = new_node
+    
+    def popleft(self):
+        if self.front is not None:
+            prev_front = self.front
+
+            prev_node_in_queue = self.front.prev_node
+            self.front.next_node = None
+            self.front.prev_node = None
+            if prev_node_in_queue is not None:
+                prev_node_in_queue.next_node = None
+
+            self.front = prev_node_in_queue
+            
+            return prev_front
+        else:
+            return None
+
+    def print_queue(self):
+        current_node = self.front
+        while current_node is not None:
+            print(current_node.value)
+            current_node = current_node.prev_node
+
+
+queue = Queue()
+queue.append("first")
+queue.append("second")
+queue.append("third")
+queue.popleft()
+queue.popleft()
+queue.print_queue()