diff --git a/src/holt59/aoc/2024/day9.py b/src/holt59/aoc/2024/day9.py
index 3ab9d39..ea1faaa 100644
--- a/src/holt59/aoc/2024/day9.py
+++ b/src/holt59/aoc/2024/day9.py
@@ -42,7 +42,7 @@ class Solver(BaseSolver):
 
         contents = contents_0.copy()
 
-        for block_start, block_length in blocks[::-1]:
+        for block_start, block_length in self.progress.wrap(blocks[::-1]):
             try:
                 i_free = next(
                     i_free
@@ -54,11 +54,10 @@ class Solver(BaseSolver):
 
             free_start, free_length = frees[i_free]
 
-            for i in range(block_length):
-                contents[free_start + i], contents[block_start + i] = (
-                    contents[block_start + i],
-                    None,
-                )
+            contents[free_start : free_start + block_length] = contents[
+                block_start : block_start + block_length
+            ]
+            contents[block_start : block_start + block_length] = [None] * block_length
 
             if free_length == block_length:
                 del frees[i_free]