From c7d939104f8fffb0a7f6ee6f8fd0b7093436e616 Mon Sep 17 00:00:00 2001
From: Jan Renz <jan.renz@gmail.com>
Date: Thu, 23 Apr 2015 15:43:23 +0200
Subject: [PATCH] handle 0 max score

---
 app/models/submission.rb | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/app/models/submission.rb b/app/models/submission.rb
index c347c503..8ee7c541 100644
--- a/app/models/submission.rb
+++ b/app/models/submission.rb
@@ -38,7 +38,11 @@ class Submission < ActiveRecord::Base
   end
 
   def normalized_score
-    score / exercise.maximum_score if score
+    if score && exercise.maximum_score && exercise.maximum_score > 0
+      score / exercise.maximum_score
+    else
+      0
+    return
   end
 
   def percentage