Old ACM programming contest question

pw1972 writes: "Years back I used to participate in old college ACM programming contests. I was always very mediocre at these contests, but enjoyed them very much. The basic idea was you have some problems to solve in a short period of time using a a watered down subset of the C programming language(no system calls, file i/o, just some standard C libraries). There is one problem that I distinctly remember and never found a solution to. I wanted to ask the Slashdot community to see what kind of creative soulutions they would have. The problem was something along the lines of: Write a program where the output of the program is the source code that you use to compile it. Reading from the source file is not allowed."