Grammar corrections

Author: baydrea

doc/attr.xml

@@ -921,11 +921,11 @@ gap> DigraphShortestDistances(D);
     <Example><![CDATA[
 gap> D := Digraph([[1, 2], [3], [1, 2], [4]]);
 <immutable digraph with 4 vertices, 6 edges>
-gap> UnweightedBellmanFord(D,2)
+gap> UnweightedBellmanFord(D, 2)
 [ [ 2, 0, 1, fail ], [ 3, fail, 2, fail ] ]
 gap> D := CycleDigraph(IsMutableDigraph, 3);
 <mutable digraph with 3 vertices, 3 edges>
-gap> UnweightedBellmanFord(D,3);
+gap> UnweightedBellmanFord(D, 3);
 [ [ 1, 2, 0 ], [ 3, 1, fail ] ]
 ]]></Example>
   </Description>