diff --git a/graph/hopcroft_karp.cpp b/graph/hopcroft_karp.cpp
index b3caf829e..40c0795fa 100644
--- a/graph/hopcroft_karp.cpp
+++ b/graph/hopcroft_karp.cpp
@@ -25,7 +25,7 @@
  * All single edge paths that start and end with free vertices are augmenting paths.
  * 
  * 
- * ###Concept :
+ * ### Concept
  * A matching M is not maximum if there exists an augmenting path. It is also true other way,
  * i.e, a matching is maximum if no augmenting path exists.
  *