Fricas

A grade

{ 1, 2, 3, 4, 10, 11, 16, 17, 18, 19 }

B grade

{ 5, 6, 7, 8, 9, 12, 13, 14, 21 }

C grade

{ 15, 20 }

F normal fail

{ }

F(-1) timedout fail

{ }

F(-2) exception fail

{ }