每次有判题任务完成的时候，递归调用自己判断还有没有等待的任务

judge_dispatcher/migrations/0002_auto_20151207_2310.py

@@ -0,0 +1,32 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('judge_dispatcher', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='judgewaitingqueue',
+            name='memory_limit',
+            field=models.IntegerField(default=1),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='judgewaitingqueue',
+            name='test_case_id',
+            field=models.CharField(default=1, max_length=40),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='judgewaitingqueue',
+            name='time_limit',
+            field=models.IntegerField(default=1),
+            preserve_default=False,
+        ),
+    ]