*public* CSP = List(Comment) Preamble List(Constraint) EOF. *public* Comment = "c" Line . *public* Preamble = "p" int int . *public* Constraint = Relation [Weight] ":" List(Variable) "0" . // relation is 0 to 255 inclusive *public* Relation = int . // weight is 1 if not specified *public* Weight = int . // variable is between 1 and numVariables inclusive *public* Variable = int . *public* List(S) ~ {S}. *public* Main = . //# Sample input file //c start with comments //p 4 3 //22: 1 2 3 0 //85 5: 1 4 0 //255 1:0