Notes on Homework 4.

• Test Cases
  • You can run the test cases by logging into cslab103 and using my test scripts.
  • To do this, change to your program directory and compile your program.
  • Then issue the command: (assuming your program is called hw4).

     ~dbennett/230/hw4/run hw4
            

• If you wish to fix your program for resubmission, you must resubmit the program by November 6.
  • Your program must run on all cases without errors.
  • Your program must compile without errors or warnings with the supplied makefile.
  • Your program must contain all suggested improvements in the notes.
  • If you fail to comply with any of the above requirements, your program will not be regraded.
• You must submit a single tar file containing both your source code and the makefile.
  • If you fail to do this, your program will not be regraded.
  • If you do not know how to do this, please see your instructor.
• If you do not understand the feedback provided, or you do not know how to act on this feedback, please see your instructor.
• You should look for opportunities to make small functions.
• Don't use 65, use 'A',
  • Given the nature of the program, a programmer will understand 'A'
  • They probably do not have the ascii table memorized however.
  • Code like this is hard to understand.

  • if(code <  65) {
         code += 26;
    } else if (code > 90) {
         code -= 26;
    } 

  • This is somewhat easier

  • if(code <  'A') {
         code += ALPHABET_SIZE ;
    } else if (code > 'Z') {
         code -= ALPHABET_SIZE; 
    } 

• If you do your offset computations in a char you can get numeric overflow for the wrong shift amount.
  • Far better to work in an int and cast.
• stream.ignore(1000,'\n') will allow a getline following a stream extraction operator.