Handling preprocessor directives.



Write a program that processes a preprocessor directive in the file containing the program in C. Should properly handle the directive # include, # define, # ifdef and ifndef.



In the implementation of # define macro functions do not require treatment.



In the implementation of # include nesting should be supported by any standard way. The standard way to headers can be specified by the environment variable INCLUDE or the command line.

Program processing text files.



All Programs in this section read data from the input text file, convert it in some way and write the result in the output file.



For all programs in this section, the last two command-line option - input file name and output file name. If not specified the input file name, then the data is read from standard input. If not specified the output file name, then the result is printed to standard output.