MODULE Ch2 EXPORTS Main;

IMPORT SIO;

VAR
  A1:ARRAY[0..3] OF CARDINAL := ARRAY OF CARDINAL{1,2,1,0};
  A2:ARRAY[0..2] OF CARDINAL := ARRAY OF CARDINAL{0,3,0};

PROCEDURE DigitCountValue(VAR A:ARRAY OF CARDINAL):BOOLEAN =
  VAR
    Hash:ARRAY[0..9] OF CARDINAL := ARRAY[0..9] OF CARDINAL{0,..};
  BEGIN
    FOR I := FIRST(A) TO LAST(A) DO INC(Hash[A[I] MOD 10]) END;
    FOR I := FIRST(A) TO LAST(A) DO
      IF Hash[I] # A[I] THEN RETURN FALSE END
    END;
    RETURN TRUE
  END DigitCountValue;

BEGIN
  SIO.PutBool(DigitCountValue(A1)); SIO.Nl();
  SIO.PutBool(DigitCountValue(A2)); SIO.Nl()
END Ch2.