diff --git a/src/assignments/assignment01.rs b/src/assignments/assignment01.rs
index de85559..5d04702 100644
--- a/src/assignments/assignment01.rs
+++ b/src/assignments/assignment01.rs
@@ -13,7 +13,7 @@ pub(crate) fn add(lhs: usize, rhs: usize) -> usize {
     todo!()
 }
 
-/// Adds two unsigned words. If underflow happens, just wrap around.
+/// Subtracts two unsigned words. If overflow happens, just wrap around.
 pub(crate) fn sub(lhs: usize, rhs: usize) -> usize {
     todo!()
 }
diff --git a/src/assignments/assignment01_grade.rs b/src/assignments/assignment01_grade.rs
index 327494b..74abedb 100644
--- a/src/assignments/assignment01_grade.rs
+++ b/src/assignments/assignment01_grade.rs
@@ -18,7 +18,7 @@ mod test {
     }
 
     #[test]
-    fn sub_underflow() {
+    fn sub_overflow() {
         assert_eq!(sub(usize::MIN, 1), usize::MAX);
     }
 }