Christian Stigen Larsen cslarsen

In "Reflections on trusting trust" --- http://cm.bell-labs.com/who/ken/trust.html --- Ken Thompson urges the reader to try write a quine. If you haven't done so yet, please try before reading on.

Here are two quines I made (without cheating), loosely based on the same idea, that I wrote in C. The first one is macro-based, utilizing the ability for macros to quote parameters:

#define Q(x) #x;x
char *q=Q(main(){printf("#define Q(x) #x;x\nchar *q=Q(");printf(q);printf(")\n");})

Compiling and running it produces an exact copy of itself:

~/devel/quine csl$ gcc --no-warnings shortq.c -o shortq && ./shortq

	/*
	* Print all permutations of string ``sÂ´Â´. (C++)
	*
	* Solved as a counting problem and coded in a hurry.
	*
	* A more elegant and recursive solution:
	* http://nicolas-lara.blogspot.com/2009/01/permutations.html
	*/

	#include <stdio.h>

	/*
	* Reverse singly linked list. (C)
	*
	* Written in a hurry after reading this HN thread:
	* http://news.ycombinator.com/item?id=1471988
	*
	*/

	#include <stdio.h>
	#include <stdlib.h>

	/*
	* Find the longest palindrome in the text.
	*
	* This is Greplin's first challenge, and I originally solved it in Python.
	*
	* The algorithm is not optimal, but simple on the eyes and easy to understand
	* On big inputs it's possible to use an approximately linear algorithm.
	*
	* Christian Stigen Larsen
	*/

	/*
	* Find the longest palindrome in the text.
	*
	* This is Greplin's first challenge, and I originally solved it in Python.
	*
	* This algorithm is linear on the average input, but has a quadratic
	* worst case running time. There exists an even better algorithm, but
	* this should do.
	*
	* There might also be a small error below, but you get the general idea.

	/*
	* A simple sieve of Eratosthenes using bitsets, written by Christian Stigen Larsen
	* You are free to use this code for anything (i.e., public domain).
	*/

	#ifndef INC_PRIMES_H
	#define INC_PRIMES_H

	#include <vector>
	#include <algorithm>

	/*
	* FizzBuzz
	*/

	#include <stdio.h>

	char* bits(int n)
	{
	#define BITS 8
	#define BIT(x) (x? '1' : ' ');

	#!/usr/bin/env python
	# -- coding: iso-8859-1 --

	"""
	Written by Christian Stigen Larsen, http://csl.sublevel3.org
	Placed in the public domain by the author

	This is a version of the classic game of guessing which animal you
	are thinking about. It uses a binary tree to guess.

	% MetaPost free body diagram with frictional forces
	%
	% Placed in the public domain by the author; Christian Stigen Larsen
	% 2011-10-07
	%
	% To render:
	% $ mptopdf free-body.mp
	%

	beginfig(1)

	/*
	* A simple sieve of Eratosthenes using bitsets, written by Christian Stigen Larsen
	* You are free to use this code for anything (i.e., public domain).
	*
	* This sieve allocates the bitset on the heap, so you can calculate a lot
	* of prime numbers.
	*/

	#ifndef INC_PRIMES_H
	#define INC_PRIMES_H