29

您的任务是创建一个打印“ Greetings，Planet！”的程序。完全在控制台上。看起来很简单，对吧？好吧，这就是窍门。该代码必须是回文，这意味着它从右到左的读取方式与从左到右的读取方式相同。标准的漏洞是不是允许。

— 小鱼
source

这似乎不是“ hello world”。

— 暴民埃里克（Erik the Outgolfer）'16年

4

@ΈρικΚωνσταντόπουλος它在所有意图和目的上都与Hello World相同。目的是打印由两个单词组成的短字符串，并且在Hello World程序中也使用常见的标点符号。除了打印Hello World的内置程序外，解决方案将完全相同（除了实际的字符串），而不管实际打印的字符串是什么。（我假设“ Greetings，Planet！”一词的选择是为了使内置插件毫无用处。）

— Martin Ender

1

@MartinBüttner我认为，Hello, world!和Hello World!是允许的唯一输出你好世界节目。

— 暴民埃里克

33

///，37字节

Greetings, Planet!/!tenalP ,sgniteerG

— 丹尼斯
source

10

这将很难被击败。

— PhiNotPi 2015年

16

TI-BASIC，67字节

"!tenalP ,sgniteerG"
"Greetings, Planet!"

之所以可行，是因为程序的最后一行显示在屏幕上，而第一个字符串实际上被视为注释。

每个小写字母存储为2个字节，其余字符为1个字节。如果我要弯腰规则并大写字母，那将是41个字节：

"!TENALP ,SGNITEERG"
"GREETINGS, PLANET!"

— 忍者熊猴子
source

您可以使用e和i（数字）进一步减少字节数吗？

— 艾迪生·克伦普

1

我考虑了@VTCAKAVSMoACE，但它们用斜体表示，因此外观略有不同。

— NinjaBearMonkey 2015年

为了清楚起见，第一行不是注释，它存储在answer变量中。

— 朱利安·拉希尼特

12

我知道这有点晚了（有点挑剔），但是...

> <>（鱼），47 45 47字节（如果我不使用随机方向，则为43 45）

x"!tenalP ,sgniteerG"!|o|!"Greetings, Planet!"x

这些答案彼此有点不同。有可能执行任一方向的代码。

因此，通过“打印到控制台”，我假设您的意思是打印到标准输出。这会引发错误；将字符串打印到stdout之后，该错误将引发stderr。

为了证明这两种方法均有效，我使用了“随机方向”导演“ x”。Fish是一种二维语言，因此，无论导演指向哪种方式，代码都仍将（最终）被执行。

假设第一个导演指向右边，则将字符以相反的顺序加载到“堆栈”中，然后打印出相反的字符（或普通文本）。

假设两个导演都指向左侧，则再次将字符以相反的顺序加载到“堆栈”中（因为代码在这里反向加载，方向是向左），然后是相反的方向（或普通文字）。

如果随机导向器向上或向下指向，则无所谓-Fish知道循环到代码的下侧或上侧，指向随机化器。这样，它将继续与随机化器循环，直到它指向内部，指向要执行的代码。

该!|o|!钻头从两侧进行以下操作：

!跳过下一条指令（将始终跳过|）
|是反射器；它向内指向o。
o 将堆栈中的当前项目作为字符输出到控制台，并将其从堆栈中删除。

因此，从本质上讲，这就是“将浴室中的两个镜子压在一起”的把戏，我一直输出到无法再用。

~~现在使用猫表情符号。>o<将输出无限地向内重定向，仍然会引发错误，但是我可以不用跳过反射就可以逃脱。~~

原来我第一次是对的-第二次尝试不是回文式的，但是反思性的。

鱼（不打印到stderr），64字节（ew）

x"!tenalP ,sgniteerG"!;oooooooooooooooooo;!"Greetings, Planet!"x

这个家伙有点长。

它具有相同的随机箭头功能（以证明它可以双向运行），并且不会打印到stderr。

这里的区别是显而易见的。我从字面上打印出堆栈中的每个项目，然后以结束执行;。

在!;不立即结束执行，就!跳过下一个项目（端EXEC，在这种情况下），并继续直到它碰到的另一侧，其用作;!，其中它结束执行它跳过任何东西之前。

它遵循与较短答案相同的随机方向模式。

— 艾迪生·克鲁普（Addison Crump）
source

我认为您应该使用语言> <>来将其与Fish shell

— Aaron

@Aaron通常假定Fish在这里表示> <>，但是我之前遇到过这个问题-我将其添加。谢谢！

— Addison Crump 2015年

就像我猜想的那样，完整的代码是否会被执行是不可估量的。如果程序计数器卡在两个随机方向指令之间，或者只是卡在随机方向指令之一中，例如，它变小，到达底部，返回到该指令并重新开始，该怎么办？

@GLASSIC该程序将只输出一次，并且整个代码将永远不会执行。

— Addison Crump

11

泡泡糖，38个字节

0000000: 73 2f 4a 4d 2d c9 cc 4b 2f d6 51 08 c8 49 cc 4b 2d 51 04  s/JM-..K/.Q..I.K-Q.
0000013: 04 51 2d 4b cc 49 c8 08 51 d6 2f 4b cc c9 2d 4d 4a 2f 73  .Q-K.I..Q./K..-MJ/s

— 丹尼斯
source

10

通心粉0.0.2字节

print "Greetings, Planet!""!tenalP ,sgniteerG" tnirp

不使用注释的解决方案。（主要是因为通心粉没有评论...）

— 门把手
source

15

通心粉没有评论？ಠ_ಠ

— 亚历A.

8

CJam，41个字节

感谢Dennis提供了三个字节。

"!tenalP ,sgniteerG";"Greetings, Planet!"

— The_Basset_Hound
source

2

您需要翻转字符串。现在，您将弹出正确的输出并打印反转的输出。

— NinjaBearMonkey

@NinjaBearMonkey哎呀。定影。

— The_Basset_Hound 2015年

也可以在GolfScript中使用。

— Ilmari Karonen 2015年

7

Foo，39个字节

"Greetings, Planet!"!tenalP ,sgniteerG"

Try it online.

— a spaghetto
source

!tenalP ,sgniteerG"Greetings, Planet! saves a few bytes.

— Dennis

6

JavaScript, 56 bytes

This can run in any browser.

alert("Greetings, Planet!")//)"!tenalP ,sgniteerG"(trela

— Downgoat
source

Replacing print/tnirp with alert/trela, it works in other engines, too.

— ETHproductions

@ETHproductions can't believe I didn't think of that, thanks!

— Downgoat

2

Template Strings? demo

— jrich

@jrich your're right, alert`Greetings, Planet!`//`!tenalP ,sgniteerG`trela is 52 bytes

— Aᴄʜᴇʀᴏɴғᴀɪʟ

5

GolfScript, 41 bytes

"Greetings, Planet!":"!tenalP ,sgniteerG"

Look ma, no no-ops! Try it online in Web GolfScript.

The second half of the source code stores the string in the second string.

"Greetings, Planet!":"!tenalP ,sgniteerG"
"!tenalP ,sgniteerG"

would print

Greetings, Planet!Greetings, Planet!

— Dennis
source

5

C++, 129 bytes

Trying to do this without comments led me into a deep, dark preprocessor nightmare with no way out that I could see. Instead I've just aimed to get it as short as possible.

/**/
#include<cstdio>
int main(){puts("Greetings Planet!");}//*/
/*//};)"!tenalP sgniteerG"(stup{)(niam tni
>oidtsc<edulcni#
/**/

— Luke
source

5

Python 3, 57 bytes

print('Greetings, Planet!')#)'!tenalP ,sgniteerG'(tnirp

I fixed the issue with parenthesis.

Python 2, 53 bytes

print'Greetings, Planet!'#'!tenalP ,sgniteerG'tnirp

I used advantage of the lack of required parenthesis and spaces in Python 2, but there wasn't that big of a difference.

— Noomann
source

5

Jelly, non-competing

25 bytes This answer is non-competing, since the challenge predates the creation of Jelly.

»1ị“RsẈḄ,#ʠU“Uʠ#,ḄẈsR“ị1»

Look 'ma, no comments! Try it online!

How it works

»1ị“RsẈḄ,#ʠU“Uʠ#,ḄẈsR“ị1»  Main link. No arguments.

   “        “        “  »  Decompress all three strings; yield a list of strings.
    RsẈḄ,#ʠU               (decompresses to 'Greetings, Planet!')
             Uʠ#,ḄẈsR      (decompresses to ' WafdkmC Posited,')
                      ị1   (decompresses to 'Taarhus')

»1                         Take the maximum of the default argument (0) and 1.
  ị                        Select the string at the index to the left.

— Dennis
source

4

Stuck, 41 Bytes

"Greetings, Planet!"p"!tenalP ,sgniteerG"

Fairly similar to the CJam answer, except in Stuck if a print command is issued, automatic stack printing is suppressed.

— Kade
source

3

Mathematica, 52 bytes

Print@"Greetings, Planet!""!tenalP ,sgniteerG"@tnirP

Also generates a Null "!tenalP ,sgniteerG"[tnirP] which doesn't get printed.

— LegionMammal978
source

1

FYI, a lot of your answers (this one included) have been getting tossed in the Low Quality queue because they're solely a title/score and code. Though there's nothing wrong with that, you may consider adding more text (such as an explanation) so they don't get auto-flagged.

— Mego

@Mego Okay, thought they were pretty self-explanatory.

— LegionMammal978

1

I'm not saying the lack of an explanation is a bad thing (though answers with explanations tend to get more upvotes), I'm just letting you know that your (valid) answers were getting auto-flagged because of their length. :)

— Mego

2

you can save 2 bytes with Echo in v10.3.

— shrx

3

Fission, 45 43 bytes

Thanks to jimmy23013 for saving 2 bytes.

;"!tenalP ,sgniteerG"R"Greetings, Planet!";

Try it online!

R initialises an atom which moves to the right. " toggles string mode which simply prints the desired string to STDOUT before hitting ;, which destroys the atom and terminates the program. The first half is simply never executed.

— Martin Ender
source

@jimmy23013 I have no clue, to be honest. Thanks.

— Martin Ender

3

05AB1E, 16 bytes

Code:

”!º¥,ÁÙ””ÙÁ,¥º!”

Explanation:

”!º¥,ÁÙ”          # Compressed string which results in "! Crm, Everywhere".
        ”ÙÁ,¥º!”  # Compressed string which results in "Greetings, Planet!".
                  # Top of stack is implicitly outputted.

Try it online!

— Adnan
source

2

STATA, 52 bytes

di "Greetings, Planet!"//"!tenalP ,sgniteerG" id

A slightly longer (53 byte) version that doesn't use comments is:

#d
di "Greetings, Planet!";"!tenalP ,sgniteerG" id
d#

#d [something] changes the delimiter (initially a carriage return) to ; unless [something] is cr, so the first command changes the delimiter to ;, the second prints the string, and the third (which continues until the end) is apparently a nop, though I have no idea why. I would have guessed that this would throw an error (unrecognized command "!tenalP ,sgniteerG" or something), but apparently not.

— bmarks
source

2

Japt, 29 bytes

^{This programming language was made after the question was posted, but was not made for this question.}

`!t?ÓP ,?Ä>ÎG`;`GÎ>Ä?, PÓ?t!`

Try it online!

Each ? is an unprintable Unicode char: U+0082, U+000F, U+000F, and U+0082, respectively.

Fun fact: If Japt had been published a month sooner, it would have legitimately won this challenge.

— ETHproductions
source

2

APL, 41 bytes

'Greetings, Planet!'⍝'!tenalP ,sgniteerG'

In APL, the last value is printed and the lamp character (⍝) start a comment.

— TuxCrafting
source

Hello, and welcome to PPCG! Great answer!

— NoOneIsHere

2

GolfScript, 41 bytes

"Greetings, Planet!"#"!tenalP ,sgniteerG"

Try it online !

— Lordmusic Player
source

@muddyfish Edited. Now it is a palindrome . Sorry.

— Lordmusic Player

2

TCL, 80 Bytes

proc unknown args {puts "Hello World!"}
}"!dlroW olleH" stup{ sgra nwonknu corp

explanation: TCL executes a global proc unknown when it encounters a call to an undefined command, the first line redefines that proc to a simple "hello world" program.

TCL's quoting rules are quite subtle, an open brace starts a quoted word that extends to the next matching close brace, allowing nested, quoted words. Braces are otherwise treated as normal characters. five words: }"!dlroW olleH", stup{, sgra, nwonknu and corp. No command named }"!dlroW olleH" has been defined, so the undefined proc from the first line is invoked instead.

A similar question was posted on the StackOverflow of antiquity; which has since been closed and deleted. I used my solution as a tongue in cheek TCL sample in this answer, and am now getting comments asking for an explanation, so I recreate my answer here.

— SingleNegationElimination
source

2

Keg, 41 bytes

Greetings\, Planet\!#!\tenalP ,\sgniteerG

Try it online!

— A̲̲
source

Try it online!

— Jono 2906

1

Vitsy, 41 Bytes

_{This programming language was made after the question was posted, but was not made for this question.}

"!tenalP ,sgniteerG"Z"Greetings, Planet!"

The Z character outputs everything in the stack to STDOUT.

Try it online!

— Addison Crump
source

1

Unefunge 98 - 49 bytes

"!tenalP ,sgniteerG<DC1>"k,@,k"<DC1>Greetings, Planet!"

The code above contains two unprintable characters with code 17 (device control 1) represented by <DC1>.

— pppery
source

1

MSM, 73 bytes

GGreetings, Planet!.................,.................!tenalP ,sgniteerGG

The first half just before the middle , builds a reverse greeting string including the additional G on the very right. The middle , drops it and the rest is a canonical "Hello/Greeting/whatever" program. The additional characters on both ends are needed, because the message contains a ,. The left one is executed and drops the s. Both , and s need a replacement for the left concatenation dots, hence the Gs. The , on the right isn't executed, but build into the final string.

— nimi
source

1

CoffeeScript, 53 bytes

Similar to Ruby and Lua and pretty much all the variants here.

alert 'Greetings, Planet!'#'!tenalP ,sgniteerG' trela

— rink.attendant.6
source

1

Ruby, 43 bytes

p"Greetings, Planet!"#"!tenalP ,sgniteerG"p

— CocoaBean
source

1

Bash, 52 48 bytes

echo Greetings, Planet!||!tenalP ,sgniteerG ohce

Also works in ksh, zsh, yash, dash. But not tcsh.

$ cat x.sh
echo Greetings, Planet!||!tenalP ,sgniteerG ohce
$ bash x.sh
Greetings, Planet!
$ ksh x.sh
Greetings, Planet!
$ zsh x.sh
Greetings, Planet!
$ yash x.sh
Greetings, Planet!
$ dash x.sh
Greetings, Planet!
$ tcsh x.sh
tenalP: Event not found.
$

— steve
source

1

Remove all quotes.

— manatwork

1

Oh dear, a bash answer was shorter than python =/. Back to the drawing board!

— Ashwin Gupta

1

Lua, 52 Bytes

print"Greetings, Planet!"--"!tenalP ,sgniteerG"tnirp

In Lua terminal, it is only 44 bytes with

="Greetings, Planet!"--"!tenalP ,sgniteerG"=

— Digital Veer
source

My bad. Thanks for the alert!

— Digital Veer

Remove all parentheses. For functions with a single string parameter they are optional.

— manatwork

Lua 5.3 do not require = in terminal, so it is 2 bytes off there. I think it existed in 2015, not sure tho.

— val says Reinstate Monica

1

Milky Way 1.5.10, 43 41 39 bytes

"Greetings, Planet!"!tenalP ,sgniteerG"

Explanation

"Greetings, Planet!"                       # push the string to the stack
                    !                      # output the TOS
                     tenalP ,sgniteerG"    # throws an error and exits

Usage

python3 milkyway.py <path-to-code>

— Zach Gates
source

Did you really need a comment? If this is stack based (without implicit output), then just outputting the stack should work.

— Addison Crump

You're right! Thanks. @FlagAsSpam

— Zach Gates

回文您好，世界

///，37字节

TI-BASIC，67字节

> <>（鱼），47 45 47字节（如果我不使用随机方向，则为43 45）

鱼（不打印到stderr），64字节（ew）

泡泡糖，38个字节

通心粉0.0.2字节

CJam，41个字节

Foo，39个字节

JavaScript, 56 bytes

GolfScript, 41 bytes

C++, 129 bytes

Python 3, 57 bytes

Python 2, 53 bytes

Jelly, non-competing

How it works

Stuck, 41 Bytes

Mathematica, 52 bytes

Fission, 45 43 bytes

05AB1E, 16 bytes

STATA, 52 bytes

Japt, 29 bytes

APL, 41 bytes

GolfScript, 41 bytes

TCL, 80 Bytes

Keg, 41 bytes

Vitsy, 41 Bytes

Unefunge 98 - 49 bytes

MSM, 73 bytes

CoffeeScript, 53 bytes

Ruby, 43 bytes

Bash, 52 48 bytes

Lua, 52 Bytes

Milky Way 1.5.10, 43 41 39 bytes

Explanation

Usage