diff --git a/src/Nikhil b/src/Nikhil
deleted file mode 160000
index 451919af139ffb9a55622886162d70e2de41c1b2..0000000000000000000000000000000000000000
--- a/src/Nikhil
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 451919af139ffb9a55622886162d70e2de41c1b2
diff --git a/src/panda_teaching b/src/panda_teaching
deleted file mode 160000
index ac09bc488b23cf4655b03e77fe2c19e0645c4983..0000000000000000000000000000000000000000
--- a/src/panda_teaching
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit ac09bc488b23cf4655b03e77fe2c19e0645c4983
diff --git a/src/zero b/src/zero
index d87f970baa2fa57c42f109cfc6196f08d82a8dc8..37009996cb0b006348fdce6c4ff26bda83922d84 160000
--- a/src/zero
+++ b/src/zero
@@ -1 +1 @@
-Subproject commit d87f970baa2fa57c42f109cfc6196f08d82a8dc8
+Subproject commit 37009996cb0b006348fdce6c4ff26bda83922d84
diff --git a/zero b/zero
new file mode 160000
index 0000000000000000000000000000000000000000..37009996cb0b006348fdce6c4ff26bda83922d84
--- /dev/null
+++ b/zero
@@ -0,0 +1 @@
+Subproject commit 37009996cb0b006348fdce6c4ff26bda83922d84