Beginning students learning the C programming language could use help with the following.

• identifying errors in a meaningful manner
• avoiding bad usage of the language
• using a correct and consistent style
• using printf and scanf correctly

Use a collection of regular expressions to do pattern matching for certain features of the program and then create output that can be transformed into something meaningful.

The data to be analyzed for test is a large collection of programs submitted by students.

The real time data will eventually be programs that students are developing for class requirements.

The languages that might be be best used for these projects include the following.

• Python : off-line static processing
• PHP: server-side processing
• JavaScript: client-side processing

Checking style usage, say for braces, could be done as follows.

• Pass 1: determine the style being used
• Pass 2: pretty print the program using that style
• Check: Use LCS (Longest Common Subsequence) algorithm, also called the MED (Minimum Edit Distance) algorithm, to determine deviations from the used style and the desired style (i.e., style errors).
• Provide diagnostics in a meaningful manner.

Checking the usage of printf and scanf can be done as follows.

• Use regular expressions to determine declared variables and types.
• Use regular expressions to determine printf and scanf statements.
• Use regular expressions to separate the parts of the printf and scanf statements.
• Check validity of the printf and scanf statements.
• Provide diagnostics in a meaningful manner.

• Use regular expressions to do simple parsing of the language.
• Look for the usage of the equal sign in other than as an assignment operator.
• Provide diagnostics in a meaningful manner.

The assignment statement in the condition always succeeds. The else part will never be executed.

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