diff --git a/code/python/src/algorithms/rucksack/display.py b/code/python/src/algorithms/rucksack/display.py
index 4607143..96ca3d2 100644
--- a/code/python/src/algorithms/rucksack/display.py
+++ b/code/python/src/algorithms/rucksack/display.py
@@ -168,7 +168,7 @@ def display_sum(
         parts = list(filter(lambda x: x[1] > 0, parts));
 
     value = sum([ u*x for _, u, x in parts ]);
-    expr = '\x1b[2m+\x1b[0m'.join(map(render, parts));
+    expr = '\x1b[2m + \x1b[0m'.join(map(render, parts));
 
     if as_maximum:
         return f'\x1b[2m=\x1b[0m {expr}';