Invalid values

Run the following DATA step to create a SAS data set called GOOD_BAD. Valid characters in the string ANSWER are ABC. abc, and 0123456789. Note that ANSWER is 40 bytes in length, and you want to ignore trailing blanks (embedded blanks are to be flagged as errors). Write a SAS DATA step to read in observations from GOOD_BAD, and create two data sets, VALID and INVALID. Place any invalid values of ANSWER in INVALID and place valid values in VALID. Lines 1 and 3 will wind up in VALID; the remaining lines will be in INVALID. (HINT: The TRIM and VERIFY Functions will be useful.)