Fix some undef warnings

diff --git a/gruntmaster-problem b/gruntmaster-problem
index f6d86dc8ac5db491059cd3c64dc57ecfa2ddb188..c3ee8def87efbe561ea8c239dc01ae54a9f431ad 100755 (executable)
--- a/gruntmaster-problem
+++ b/gruntmaster-problem
@@ -166,10 +166,10 @@ sub cmd_check {
                }
        }
 
-       say 'Max time for AC: ' . max @good_times;
-       say 'Min time for TLE: ' . min @fail_times;
+       say 'Max time for AC: ' . max @good_times if @good_times;
+       say 'Min time for TLE: ' . min @fail_times if @fail_times;
        say $fail ? 'Test failed' : 'Test successful';
-       exit $fail;
+       exit $fail if $fail;
 }
 
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