1 files changed, 1 insertions, 1 deletions
diff --git a/tit4tat.pl b/tit4tat.pl
index b997a00..ec0eccb 100644
--- a/tit4tat.pl
+++ b/tit4tat.pl
@@ -36,7 +36,7 @@ tit4tat(A, Hist, PayA, PayB) :-
 	pay2(A, Old, PayA, PayB).
 
 sum([], 0).
-sum([H|T], S):-sum(T, TMP), S is TMP + H.
+sum([H|T], S) :- sum(T, TMP), S is TMP + H.
 
 loop(end, _).
 loop(End, Hist, PayedA, PayedB):- End\=end,