fix Makefile and README.md for 2000/primenum
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@@ -1,215 +1,327 @@
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#!/bin/make
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# 2000 makefile
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#!/usr/bin/env make
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#
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# Copyright (C) Simon Cooper, Landon Curt Noll, Peter Seebach
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# and Leonid A. Broukhis, 2000.
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# All Rights Reserved. Permission for personal, educational or non-profit
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# use is granted provided this this copyright and notice are included in its
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# entirety and remains unaltered. All other uses must receive prior permission
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# from the contest judges.
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# IOCCC 2000 winning entry - primenum
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SHELL= /bin/sh
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CAT= cat
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RM= rm
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SED= sed
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TRUE= true
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#CINCLUDE= -I ${HOMEBREW_PREFIX}/include/SDL2
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# optimization
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################################################################################
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#
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# Most compiles will safely use -O2. Some can use only -O.
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# A few compilers have broken optimizers and thus you may
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# not want anything.
|
||||
# Regarding individual entries:
|
||||
#
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||||
# IOCCC winning entry code may not work on your system. Even with standards,
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# conditions and build environments change, especially when it comes to more
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# extreme code such you might find in an IOCCC winner. Moreover, what was
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# allowed and liked in one IOCCC contest may no longer be liked/allowed in
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# later IOCCC years.
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#
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# Corrections on winning author and fixing typos in remarks are VERY WELCOME.
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#
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# GitHub pull requests are welcome:
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#
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# If you have a patch that might make running an entry work in modern Unix-like
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# environments, please create a GitHub pull request for the IOCCC judges to
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# consider.
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#
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# Suggestions and corrections regarding Makefiles, winning author information,
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# fixing typos in remarks, and code patches are welcome via opening a GitHub
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# issue or better yet, by creating a GitHub pull request for the IOCCC judges
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# to consider. To form a GitHub issue or GitHub pull, please visit:
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#
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# https://github.com/ioccc-src/winner
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#
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################################################################################
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# This work by Landon Curt Noll and Leonid A. Broukhis is licensed under:
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#
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# Creative Commons Attribution-ShareAlike 3.0 Unported License.
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#
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# See: http://creativecommons.org/licenses/by-sa/3.0/
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#############################
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# shell used by this Makefile
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#############################
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#
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SHELL= bash
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#######################
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# common tool locations
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#######################
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#
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include ../../var.mk
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# Set X11_LIBDIR to the directory where the X11 library resides
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#
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#X11_LIBDIR= /usr/X11R6/lib
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#X11_LIBDIR= /usr/X11/lib
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X11_LIBDIR= /opt/X11/lib
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# Set X11_INCLUDEDIR to the directory where the X11 include files reside
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#
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#X11_INCDIR= /usr/X11R6/include
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#X11_INCDIR= /usr/X11/include
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X11_INCDIR= /opt/X11/include
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# Common C compiler warnings to silence
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#
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#CSILENCE=
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CSILENCE= -Wno-error -Wno-implicit-function-declaration -Wno-main-return-type \
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-Wno-unused-parameter
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# Common C compiler warning flags
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#
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#CWARN= ${CSILENCE}
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#CWARN= -Wall ${CSILENCE}
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#CWARN= -Wall -Wextra ${CSILENCE}
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CWARN= -Wall -Wextra -pedantic ${CSILENCE}
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# Compiler standard
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#
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#CSTD=
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#CSTD= -ansi
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CSTD= -std=gnu99
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# Compiler bit architecture
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#
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# Some entries require 32-bitness:
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# ARCH= -m32
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#
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# Some entries require 64-bitness:
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# ARCH= -m64
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#
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# By default we assume nothing:
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#
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ARCH=
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# Defines that are needed to compile
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#
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CDEFINE=
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#CDEFINE= -DIOCCC
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# Include files that are needed to compile
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#
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CINCLUDE=
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#CINCLUDE= -include stdlib.h
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#CINCLUDE= -include stdio.h
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#CINCLUDE= -include stdlib.h -include stdio.h
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#CINCLUDE= -I ${X11_INCDIR} -I ${X11_INCDIR}/X11
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#CINCLUDE= `${SDL2_CONFIG} --cflags`
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# Optimization
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#
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# Most compiles will safely use -O2. Some can use only -O1 or -O.
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# A few compilers have broken optimizers or this entry make break
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# under those buggy optimizers and thus you may not want anything.
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# Reasonable compilers will allow for -O3.
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#
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#OPT=
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#OPT= -O
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OPT= -O2
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#OPT= -O1
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#OPT= -O2
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OPT= -O3
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# flags for ANSI compiles
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# Default flags for ANSI C compilation
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#
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# NOTE: Some ANSI compilers make use of -Xa to turn on ANSI mode,
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# others such as gcc may want -ansi, others (Compaq Tru64 Unix)
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# want -std1, and others may want nothing at all.
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# Adjust the CFLAGS line as needed.
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#
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# NOTE: Some compilers cannot optimize, or optimize some entries
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# incorrectly. You might want to turn on -O to see if your
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# compiler can handle them.
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#
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#
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#CFLAGS= -Xa ${OPT}
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#CFLAGS= -std1 $(OPT)
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CFLAGS= -ansi ${OPT}
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CFLAGS= ${CSTD} ${CWARN} ${ARCH} ${CDEFINE} ${CINCLUDE} ${OPT}
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NO_ANSI_CFLAGS=
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#NO_ANSI_CFLAGS=
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# Libraries needed to build
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#
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LIBS=
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#LIBS= -lm
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#LIBS= -L ${X11_LIBDIR} -lX11
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#LIBS= `${SDL2_CONFIG} --libs`
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# NOTE: On some systems, the library path does not include the location
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# of the X11 libraries. You might need to use a -L/path/to/X11/lib/dir
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# in order to compile with these libs.
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#
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X11CCFLAGS= -I/usr/X11R6/include -I/usr/X11R6/include/X11 -I/usr/include/X11
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#X11CCFLAGS=
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X11LDFLAGS= -L/usr/X11R6/lib
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#X11LDFLAGS=
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# Perl
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#
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PERL= perl
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#PERL= perl5
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# ANSI compiler
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#
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# Set CC to the name of your ANSI compiler.
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#
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# Some entries seem to need gcc. If you have gcc, set
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# both CC and MAY_NEED_GCC to gcc.
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#
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# If you do not have gcc, set CC to the name of your ANSI compiler, and
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# set MAY_NEED_GCC to either ${CC} (and hope for the best) or to just :
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# to disable such programs.
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# C compiler to use
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#
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CC= cc
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MAY_NEED_GCC= gcc
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#CC=clang
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#CC=gcc
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# winners that compile under ANSI C
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# Compiler add-ons or replacements for clang only
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#
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WINNERS= anderson schneiderwent primenum bellard bmeyer briddlebane dhyang \
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dmy2jd jarijyrki dlowe natori rince robison thadgavin tomx
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ALT_NAMES= schneiderwent.orig briddlebane.orig thadgavin.orig
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DATA_FILES= schneiderwent_files bmeyer_files jarijyrki_files
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all: ${WINNERS}
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# Best use of flags
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ifeq ($(CC),clang)
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#
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anderson: anderson.c
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${CC} ${CFLAGS} $? -o $@
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# Most Timely Output
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CSILENCE+= -Wno-implicit-int-conversion -Wno-poison-system-directories
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#
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schneiderwent: schneiderwent.c
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${CC} ${CFLAGS} $? -o $@
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schneiderwent_files: schneiderwent.data
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schneiderwent.orig: schneiderwent.orig.c
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${CC} ${CFLAGS} $? -o $@
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# Best Abuse of CPP
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CWARN+= -Weverything
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#
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primenum: primenum.c
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${CC} ${CFLAGS} $? -o $@
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endif
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# Most Specific Output
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# Specific add-ons or replacements for gcc only
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#
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bellard: bellard.c
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${CC} ${CFLAGS} $? -o $@
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ifeq ($(CC),gcc)
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#
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#CSILENCE+=
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#
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#CWARN+=
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#
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endif
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# Best Utility
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#
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# machines operating in 64 bit mode:
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#
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bmeyer: bmeyer.c
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${CC} -DY= -O6 $? -o $@ -lm
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#
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# linux/x86, glibc 2.0, libc4/5:
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#
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# bmeyer: bmeyer.c
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# ${CC} -DY="__setfpucw(0x127f)" -O6 $? -o $@ -lm
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#
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# linux/x86, glibc 2.1:
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#
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# bmeyer: bmeyer.c
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# ${MAY_NEED_GCC} -DY='int x=0x127f; __asm__ ("fldcw %0" : : "m" (*&x))' \
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# -O6 $? -o $@ -lm
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bmeyer_files: lavabus.pgm lenna.glic michael.pgm
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# Best Abuse of User
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##############################
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# Special flags for this entry
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##############################
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#
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briddlebane: briddlebane.c
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${CC} ${CFLAGS} $? -o $@ -lm
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briddlebane.orig: briddlebane.orig.c
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${CC} ${CFLAGS} $? -o $@ -lm
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# Best Layout
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ENTRY= primenum
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PROG= ${ENTRY}
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#
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dhyang: dhyang.c
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${CC} ${CFLAGS} $? -o $@
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dmy2jd: dmy2jd.c
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${CC} ${CFLAGS} $? -o $@
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# Best of Show
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OBJ= ${PROG}.o
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DATA=
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TARGET= ${PROG}
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#
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jarijyrki: jarijyrki.c
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${CC} ${X11CCFLAGS} ${CFLAGS} -DNeedFunctionPrototypes \
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-DU=40 -DT=98 '-Dz=(T+1)*U*U' -DQ=80 -DS=20 -DN=10 -DB=5 -DG=23 \
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-Dp=7 '-DM=((p+1)*Q)+S' '-DH=(G*S)+S+S' -DC=XK_Up -DL=XK_Down \
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-DO=XK_Left -DV=XK_Right -DR=XK_Escape -D_=XK_BackSpace \
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$? -o $@ ${X11LDFLAGS} -lX11
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ALT_OBJ=
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ALT_TARGET=
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jarijyrki_files: sheet1.info
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# Worst Abuse of the Rules
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#################
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# build the entry
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#################
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#
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# NOTE: You will need to adjust this path to the place where Perl has been
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# installed on your system. Running "perl -V" may help you locate
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# this place.
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#
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# The following bit of perl may help determining the values you need:
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#
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# perl -MConfig -e 'print "$Config{archlibexp}/CORE\n"'
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#
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#
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||||
dlowe: dlowe.c
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${CC} ${NO_ANSI_CFLAGS} -DPERL_POLLUTE \
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`${PERL} -MExtUtils::Embed -e ccopts` $? -o $@ \
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`${PERL} -MExtUtils::Embed -e ldopts`
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# Best Small Program
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||||
#
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||||
natori: natori.c
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${CC} ${CFLAGS} $? -o $@ -lm
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|
||||
# Astronomically Obfuscated
|
||||
#
|
||||
rince: rince.c
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${CC} ${X11CCFLAGS} ${CFLAGS} -DM_PI=3.14159265358979323846 \
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$? -o $@ -lm ${X11LDFLAGS} -lX11
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# Best game
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#
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robison: robison.c
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${CC} ${CFLAGS} $? -o $@
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# Most Portable Output
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#
|
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thadgavin: thadgavin.c
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${CC} ${CFLAGS} $? -o $@ -lcurses -lm
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thadgavin.orig: thadgavin.orig.c
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${CC} ${CFLAGS} $? -o $@ -lncurses -lm
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# Most Complete Program
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#
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tomx: tomx.c
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${CC} ${CFLAGS} $? -o $@
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everything: ${WINNERS} ${ALT_NAMES} ${DATA_FILES}
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clean:
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${RM} -f *.o a.out core ${WINNERS}
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clobber: clean
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||||
${RM} -f ${WINNERS}
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${RM} -f ${ALT_NAMES}
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|
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nuke: clobber
|
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all: data ${TARGET}
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||||
@${TRUE}
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|
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install: all
|
||||
${CAT} ${WINNERS} ${ALT_NAMES} > /dev/null
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.PHONY: all alt data everything clean clobber install \
|
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love haste waste maker easter_egg sandwich \
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supernova deep_magic magic charon pluto
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|
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${PROG}: ${PROG}.c
|
||||
${CC} ${CFLAGS} $< -o $@ ${LIBS}
|
||||
|
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# alternative executable
|
||||
#
|
||||
alt: data ${ALT_TARGET}
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@${TRUE}
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||||
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||||
# data files
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||||
#
|
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data: ${DATA}
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@${TRUE}
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||||
|
||||
# both all and alt
|
||||
#
|
||||
everything: all alt
|
||||
|
||||
|
||||
###############
|
||||
# utility rules
|
||||
###############
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||||
#
|
||||
clean:
|
||||
${RM} -f ${OBJ} ${ALT_OBJ}
|
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@-if [ -f indent.c ]; then \
|
||||
echo ${RM} -f indent.c; \
|
||||
${RM} -f indent.c; \
|
||||
fi
|
||||
|
||||
clobber: clean
|
||||
${RM} -f ${TARGET} ${ALT_TARGET}
|
||||
@-if [ -e sandwich ]; then \
|
||||
${RM} -f sandwich; \
|
||||
echo 'ate sandwich'; \
|
||||
fi
|
||||
|
||||
install:
|
||||
@echo "Dr. Spock says that is not logical!"
|
||||
@${TRUE}
|
||||
|
||||
# you may be able to misunderstand the source by reading indent.c
|
||||
#
|
||||
indent.c: ${PROG}.c
|
||||
@if which "${GINDENT}" >/dev/null 2>&1; then \
|
||||
echo ${RM} -f $@; \
|
||||
${RM} -f $@; \
|
||||
echo "${GINDENT} < $< > $@"; \
|
||||
${GINDENT} < $< > $@; \
|
||||
elif which "${INDENT}" >/dev/null 2>&1; then \
|
||||
echo ${RM} -f $@; \
|
||||
${RM} -f $@; \
|
||||
echo "${INDENT} < $< > $@"; \
|
||||
${INDENT} < $< > $@; \
|
||||
else \
|
||||
echo "no intent tool found, ident $< yourself, sorry"; \
|
||||
echo "exit 1"; \
|
||||
exit 1; \
|
||||
fi
|
||||
|
||||
|
||||
##################
|
||||
# 133t hacker rulz
|
||||
##################
|
||||
#
|
||||
love:
|
||||
@echo 'not war?'
|
||||
@${TRUE}
|
||||
|
||||
haste:
|
||||
$(MAKE) waste
|
||||
@${TRUE}
|
||||
|
||||
waste:
|
||||
@echo 'haste'
|
||||
@${TRUE}
|
||||
|
||||
maker:
|
||||
@echo 'Participate in a maker faire'
|
||||
@${TRUE}
|
||||
|
||||
easter_egg:
|
||||
@echo "you expected to often misunderstand this $${RANDOM} magic"
|
||||
@echo "chongo '<was here>' /\\oo/\\"
|
||||
@echo "Eggy"
|
||||
|
||||
sandwich: easter_egg
|
||||
@if [ `id -u` -eq 0 ]; then \
|
||||
echo 'Okay.'; \
|
||||
echo "$${RANDOM}`date +%s`$${RANDOM}" > $@; \
|
||||
else \
|
||||
echo 'What? Make it yourself.'; \
|
||||
exit 1; \
|
||||
fi
|
||||
|
||||
# Understand the history of the Homebrew Computer Club
|
||||
# as well as the West Coast Computer Faire and
|
||||
# you might be confused different. :-)
|
||||
#
|
||||
supernova: sandwich
|
||||
@-if [ -r .code_anal ]; then \
|
||||
${RM} -f .code_anal_v6; \
|
||||
else \
|
||||
echo "planet deniers, like some members of the IAU, are so cute when they try to defend their logic"; \
|
||||
fi
|
||||
@echo "A $@ helps ${MAKE} the elements that help form planets"
|
||||
@${TRUE}
|
||||
|
||||
deep_magic: supernova
|
||||
@-if [ -r .code_anal ]; then \
|
||||
ccode_analysis --deep_magic 7889066cdbdf09b0408021754586e895be641cc9be29e7eafd3ca65359541f17 \
|
||||
--FNV1a_hash_512_bit -v2 "${PROG}" "${PROG}.c"; \
|
||||
else \
|
||||
echo "Wrong! Do it again!"; \
|
||||
sleep 2; \
|
||||
echo "Wrong! Do it again!"; \
|
||||
sleep 2; \
|
||||
echo "Wrong! Do it again!"; \
|
||||
fi
|
||||
@${TRUE}
|
||||
|
||||
magic: deep_magic
|
||||
@-if [ -r .code_anal ]; then \
|
||||
ccode_analysis --level 20003 --mode 5717175 --FNV1a_hash_512_bit -v2 "${PROG}" "${PROG}.c"; \
|
||||
else \
|
||||
echo "If you don't eat yer meat, you can't have any pudding!"; \
|
||||
echo "How can you have any pudding if you don't eat yer meat?!"; \
|
||||
fi
|
||||
@${TRUE}
|
||||
|
||||
# The IOCCC resident astronomer states
|
||||
#
|
||||
charon: magic
|
||||
@echo "$@ is a dwarf planet"
|
||||
@echo "dwarf is a type of planet"
|
||||
@echo "therefore IAU, $@ is a planet"
|
||||
|
||||
pluto: charon
|
||||
${MAKE} charon
|
||||
@echo "$@ is a dwarf planet"
|
||||
@echo "dwarf is a type of planet"
|
||||
@echo "therefore, $@ is a planet"
|
||||
@echo "having lots of planets is good feature because supernovae can help ${MAKE} a lot of them"
|
||||
|
||||
+60
-53
@@ -1,75 +1,82 @@
|
||||
Best Abuse of CPP:
|
||||
# Best Abuse of CPP:
|
||||
|
||||
Raymond Cheong
|
||||
[address subject to change]
|
||||
MD, USA
|
||||
|
||||
# To build:
|
||||
|
||||
Judges' Comments:
|
||||
```sh
|
||||
make
|
||||
```
|
||||
|
||||
To build:
|
||||
### To run:
|
||||
|
||||
make primenum
|
||||
```sh
|
||||
./primenum n
|
||||
```
|
||||
NOTE: n is an integer.
|
||||
|
||||
To run:
|
||||
### Try:
|
||||
|
||||
./primenum n (where n is an integer)
|
||||
```sh
|
||||
./primenum 23209
|
||||
```
|
||||
|
||||
Don't read the author comments until you're ready for the spoiler.
|
||||
Just stop and read the program; it won't take long. Once you've figured
|
||||
out what it does, run it. It may surprise you.
|
||||
## Judges' comments:
|
||||
|
||||
This entry won, not because the obfuscation is impenetrable, but because
|
||||
it successfully fooled half of the judges, including me.
|
||||
Don't read the author comments until you're ready for the spoiler.
|
||||
Just stop and read the program; it won't take long. Once you've figured
|
||||
out what it does, run it. It may surprise you.
|
||||
|
||||
This entry won, not because the obfuscation is impenetrable, but because
|
||||
it successfully fooled half of the judges, including me.
|
||||
|
||||
Selected Author's Comments:
|
||||
## Author's comments:
|
||||
|
||||
Description
|
||||
===========
|
||||
### Description
|
||||
|
||||
For 15 years, IOCCC winners have obfuscated programs using esoteric,
|
||||
difficult-to-interpret, confusing algorithms. This entry finally bucks
|
||||
that trend and obfuscates in the most "obvious" way possible: by
|
||||
painstakenly describing the algorithm in clear pseudocode. Even novice
|
||||
programmers will recognize that the program should find and print prime
|
||||
numbers up to a given number (as specified on the command line).
|
||||
For 15 years, IOCCC winners have obfuscated programs using esoteric,
|
||||
difficult-to-interpret, confusing algorithms. This entry finally bucks
|
||||
that trend and obfuscates in the most "obvious" way possible: by
|
||||
painstakenly describing the algorithm in clear pseudocode. Even novice
|
||||
programmers will recognize that the program should find and print prime
|
||||
numbers up to a given number (as specified on the command line).
|
||||
|
||||
But novice programmers especially know that mistakes are often made in
|
||||
translating pseudocode to real code, often resulting in programs with
|
||||
unexpected and confusing output. Clearly, the program contains several
|
||||
syntax "mistakes" (e.g. LessThanOrEqualTo) and blatant "errors" (e.g.
|
||||
Zero). This program clearly requires "debugging."
|
||||
But novice programmers especially know that mistakes are often made in
|
||||
translating pseudocode to real code, often resulting in programs with
|
||||
unexpected and confusing output. Clearly, the program contains several
|
||||
syntax "mistakes" (e.g. LessThanOrEqualTo) and blatant "errors" (e.g.
|
||||
Zero). This program clearly requires "debugging."
|
||||
|
||||
As a result of these "bugs", the program does not primes at all.
|
||||
Instead, the program reads input from stdin and returns garbled text on
|
||||
stdout. Fortunately, you can recover the original message simply by
|
||||
running the program a second time. Try:
|
||||
As a result of these "bugs", the program does not primes at all.
|
||||
Instead, the program reads input from stdin and returns garbled text on
|
||||
stdout. Fortunately, you can recover the original message simply by
|
||||
running the program a second time. Try:
|
||||
|
||||
./primenum n < textfile | ./primenum n > textfile2
|
||||
diff textfile textfile2
|
||||
./primenum n < textfile | ./primenum n > textfile2
|
||||
diff textfile textfile2
|
||||
|
||||
where n is the same number (modulo 64). So, the prime number generator
|
||||
is actually a simple text encoder/decoder! Of course, don't forget that
|
||||
argument, otherwise the "bugs" in the program will cause it to crash!
|
||||
where n is the same number (modulo 64). So, the prime number generator
|
||||
is actually a simple text encoder/decoder! Of course, don't forget that
|
||||
argument, otherwise the "bugs" in the program will cause it to crash!
|
||||
|
||||
Features
|
||||
========
|
||||
### Features
|
||||
|
||||
- The program attempts to mislead the reader into thinking that it
|
||||
generates prime numbers. It does this by
|
||||
o describing a correct algorithm in pseudocode,
|
||||
o using partially correct conversion of pseudocode to real code,
|
||||
o using suggestive variable names, and
|
||||
o using a suggestive program name.
|
||||
- The program demonstrates a novel method of abusing the C preprocessor.
|
||||
- How the filter algorithm works is left as an exercise to the reader.
|
||||
- OK, so running it through the preprocessor strips away the prime
|
||||
number front. But ye be warned: not a11 variab1es1es are identica1 :-)
|
||||
- Other features include
|
||||
o useless variables
|
||||
o useless if
|
||||
o a for loop that's used as an if statement
|
||||
o dependence on the high bit being 0
|
||||
- Try also
|
||||
echo THIS MESSAGE IS IN ALL CAPS | primenum 32
|
||||
- The program attempts to mislead the reader into thinking that it
|
||||
generates prime numbers. It does this by
|
||||
o describing a correct algorithm in pseudocode,
|
||||
o using partially correct conversion of pseudocode to real code,
|
||||
o using suggestive variable names, and
|
||||
o using a suggestive program name.
|
||||
- The program demonstrates a novel method of abusing the C preprocessor.
|
||||
- How the filter algorithm works is left as an exercise to the reader.
|
||||
- OK, so running it through the preprocessor strips away the prime
|
||||
number front. But ye be warned: not a11 variab1es1es are identica1 :-)
|
||||
- Other features include
|
||||
o useless variables
|
||||
o useless if
|
||||
o a for loop that's used as an if statement
|
||||
o dependence on the high bit being 0
|
||||
- Try also
|
||||
echo THIS MESSAGE IS IN ALL CAPS | ./primenum 32
|
||||
Reference in new issue
Block a user