Is it double speak?

Question

In an earlier challenge I asked code golfers to produce strings which copy each character in a string. For example:

TThhiiss iiss ddoouubbllee ssppeeaakk!!

This challenge is simply to detect if some text meets the definition of a double speak string.

There is an even number of characters.
When split into pairs, every pair consists of two of the same character.

The challenge

It's code golf, do it in few bytes.
Use any language you choose.
Please include a link to an online interpreter.
The code will accept some text.
For simplicity, the input will only consist of printable ASCII characters
It will return an indication of whether or not the input is double speak. It could be:
A boolean
Strings ('true', 'false', 'yes', 'no' etc)
Integers 0 or 1

Test Cases:

input -> output aba -> false aab -> false abba -> false aabb -> true aaabb -> false tthhiiss -> true ttthhhiiisss -> false

\$\begingroup\$ May we error on inputs of length < 2? \$\endgroup\$

cole
– cole

2019-08-06 16:06:17 +00:00
Commented Aug 6, 2019 at 16:06 — cole
– cole, Commented Aug 6, 2019 at 16:06
\$\begingroup\$ Suggested test case: abba which should be falsey \$\endgroup\$

Giuseppe
– Giuseppe

2019-08-06 16:29:11 +00:00
Commented Aug 6, 2019 at 16:29 — Giuseppe
– Giuseppe, Commented Aug 6, 2019 at 16:29
\$\begingroup\$ Suggested test case: aabbbb which should be truthy \$\endgroup\$

Khuldraeseth na'Barya
– Khuldraeseth na'Barya

2019-08-06 17:30:04 +00:00
Commented Aug 6, 2019 at 17:30 — Khuldraeseth na'Barya
– Khuldraeseth na'Barya, Commented Aug 6, 2019 at 17:30
\$\begingroup\$ @val Well, I'm not going to argue with standard I/O \$\endgroup\$

AJFaraday
– AJFaraday

2019-08-07 08:27:01 +00:00
Commented Aug 7, 2019 at 8:27 — AJFaraday
– AJFaraday, Commented Aug 7, 2019 at 8:27
\$\begingroup\$ What about the empty string? \$\endgroup\$

PieCot
– PieCot

2019-08-07 21:04:17 +00:00
Commented Aug 7, 2019 at 21:04 — PieCot
– PieCot, Commented Aug 7, 2019 at 21:04

FunkySyntax · Accepted Answer · 2019-08-06 20:29:14Z

2

Kotlin, 56 52 bytes

{it.chunked(2).filter{it.toHashSet().size>1}.size<1}

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Thank you Khuldraeseth na'Barya for saving 4 bytes

edited Aug 6, 2019 at 20:29

answered Aug 6, 2019 at 20:11

FunkySyntax

313 bronze badges

\$\begingroup\$ Save a handful. Welcome to the site! \$\endgroup\$

Khuldraeseth na'Barya
– Khuldraeseth na'Barya

2019-08-06 20:19:31 +00:00
Commented Aug 6, 2019 at 20:19

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ErikF · Accepted Answer · 2019-08-07 08:13:12Z

2

C (gcc), 50 bytes

Returns 0 if double-speak (or empty string), truthy otherwise.

f(s,i)char*s;{for(i=*s;i&(i=*s++)&&i==*s++;);s=i;}

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If the input string is assumed to always be at least 2 characters (gives incorrect result for single-character strings):

C (gcc), 38 bytes

f(char*s){while(*s&&*s++==*s++);s=*s;}

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answered Aug 7, 2019 at 8:13

ErikF

4,7879 silver badges11 bronze badges

\$\begingroup\$ The second suggestion seems to treat single character strings the same as any other odd length strings? \$\endgroup\$

Taemyr
– Taemyr

2019-08-08 07:30:02 +00:00
Commented Aug 8, 2019 at 7:30
\$\begingroup\$ Wouldn't putting s=i at the end of for braces (for(i=*s;i&(i=*s++)&&i==*s++;s=i) save you one ;? \$\endgroup\$

Przemysław Czechowski
– Przemysław Czechowski

2019-08-08 17:47:30 +00:00
Commented Aug 8, 2019 at 17:47
\$\begingroup\$ @PrzemysławCzechowski s=i is used to return the value: it's not part of the loop. I'm using i to capture the character value, so assigning it to s during the loop would mess up the pointer (and likely crash the program!) \$\endgroup\$

ErikF
– ErikF

2019-08-08 18:04:53 +00:00
Commented Aug 8, 2019 at 18:04
\$\begingroup\$ @ErikF my bad, I thought s=i is repeated in every iteration. \$\endgroup\$

Przemysław Czechowski
– Przemysław Czechowski

2019-08-08 18:23:52 +00:00
Commented Aug 8, 2019 at 18:23

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Kenzie · Accepted Answer · 2019-08-07 15:15:05Z

Pip, 31 bytes

a:qFb,#a{b%2?x(ab+1)Qa@b?xi:1}i

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slightly different approach with fold operator, 31 bytes

a:qFb,#a{I!b%2i:$Q[a@b(ab+1)]}i

outputs 0 if double speak, 1 otherwise

Jo King · Accepted Answer · 2019-08-08 04:53:22Z

Perl 6, 14 bytes

{!S:g/(.)$0//}

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Replaces all pairs of identical characters with nothing and then boolean NOTs the result to return true if is an empty string (i.e. all characters were next to an identical one), or false otherwise.

aross · Accepted Answer · 2019-08-08 09:55:47Z

PHP, 51 50 38 bytes

echo preg_match("/^((.)\2)+$/",$argn);

Checks whether input matches pairs of chars where the chars in each pair are the same (using back ref).

Run like this:

echo 'dd00uubbllee' | php -nR 'echo preg_match("/^((.)\\2)+$/",$argn);';echo

-1 byte thanks to @manatwork
-12 bytes by using preg_match with back references.

\$\begingroup\$ Wouldn't /.(.?)/ be enough to handle odd length strings? \$\endgroup\$

manatwork
– manatwork

2019-08-08 09:29:47 +00:00
Commented Aug 8, 2019 at 9:29 — manatwork
– manatwork, Commented Aug 8, 2019 at 9:29
\$\begingroup\$ @manatwork you're right, thanks \$\endgroup\$

aross
– aross

2019-08-08 09:32:26 +00:00
Commented Aug 8, 2019 at 9:32 — aross
– aross, Commented Aug 8, 2019 at 9:32

Night2 · Accepted Answer · 2019-08-08 11:37:03Z

PHP, 37 40 bytes

+3 bytes to fix '0' issue

<?=''==preg_replace('/(.)\1/','',$argn);

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PHP, 55 bytes

for(;($l=$argn[$i++])==$argn[$i++]&&$l.$l;);echo$l=='';

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Loops to the end of the string as long as every even character (0th, 2nd, 4th, etc ...) is equal to the character after it, else stops the loop. Finally, checks if it has arrived at the end of the string, which means the string is a double speak.

Outputs 1 for double speak and nothing for not double speak.

Your first one is close, but it negates the resulting string. "0" is falsey in PHP, so an input of "000" will be deemed doublespeak — aross
– aross, Commented Aug 8, 2019 at 9:59
@aross: Thanks for pointing it out, yeah that '0' == false is always an issue. Fixed! — Night2
– Night2, Commented Aug 8, 2019 at 11:38

Olivier Grégoire · Accepted Answer · 2019-08-09 10:46:05Z

Java (JDK), 64 bytes

s->{int i=s.length;for(;i>1;)i=s[--i]==s[--i]?i:i|1;return i<1;}

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Explanations

s->{ int i=s.length; for(;i>1;) // while the length is 2 or greater. i=s[--i]==s[--i]?i:i|1; // check the 2 previous values. If they're identical, don't do anything. Else, make i odd so that it fails at the return. return i<1; // i will be 0 only when the size is even and all characters were doubled. }

Khuldraeseth na'Barya · Accepted Answer · 2019-08-28 15:19:45Z

Stax, 6 5 bytes

╩3╦x╨

Run and debug it at staxlang.xyz!

Outputs integers. Zero for double speak and nonzero (one now!) otherwise, as allowed here. Replace 1I below with |e if you want the opposite behavior, but I think this version looks nicer.

Unpacked (6 bytes) and explanation

:G|g1I :G Array of run lengths |g GCD 1I Is odd? Could use 2% instead

The GCD of run lengths will be even exactly when all run lengths are.

FlipTack · Accepted Answer · 2019-12-27 19:48:46Z

Pushy, 13 bytes

LL2%}2/:=};P#

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 L \ Push len(input) L2% \ Take (len(input) + 1) % 2. This will be 1 only if the input had even length. } \ Move this to the bottom of the stack for later. 2/: ; \ Length of original input, divided by 2, times do: = \ Pop top two characters, and check equality. (Pushes 0 or 1) } \ Move this to the bottom of the stack for later. P \ Push the stack's product. If the input had odd length, or any two characters \ did not match, then the stack will contain a 0, so the product will be 0. \ Else, it will be 1. # \ Print the product.

sporeball · Accepted Answer · 2020-01-14 03:40:12Z

naz, 50 bytes

2a2x1v1x1f1r3x1v2e2x2v1r3x2v1e0m1o0x1x2f0m1a1o0x1f

Works for any input string, provided it's passed as a file terminated with the control character STX (U+0002).

Explanation (with 0x commands removed)

2a2x1v # Set variable 1 equal to 2 1x1f1r3x1v2e # Function 1 # Read a byte and jump to function 2 if it equals variable 1 2x2v # Otherwise, store it in variable 2 1r3x2v1e # Read another byte # Jump back to the start of function 1 if it equals variable 2 0m1o # Otherwise, output 0 1x2f0m1a1o # Function 2 # Output 1 1f # Call function 1

DeathIncarnate · Accepted Answer · 2020-02-07 20:47:22Z

Burlesque, 8 bytes

J2en)J==

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 [AABBCC] [ABC] J #Duplicate [AABBCC,AABBCC] [ABC,ABC] 2en #Every other character [AABBCC,ABC] [ABC,AC] )J #Duplicated [AABBCC,AABBCC] [ABC,AACC] == #Is the same [1] [0]

Burlesque, 11 bytes

=[{L[2dv}al

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=[ # Group consecutive like values { L[ # Length of (group) 2dv # Divisible by 2 }al # All

jonatjano · Accepted Answer · 2020-09-24 20:59:27Z

Marbelous, 84 bytes

No output for false, output one \u0000 for true using this standard I/O rule

@0@1 0000 ]]]]&101 eqal\\&1 @0@1..=0\/ :eqal @0..@1 }0..}1 --..-- <1&0<1&0 {0@0{1@1

interpretor

mekb · Accepted Answer · 2021-07-15 15:34:28Z

JavaScript (Node.js), 23 bytes

z=>/^((.)\2)+$/.test(z)

Uses a regular expression that match two of the same characters one or more times

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rydwolf · Accepted Answer · 2022-02-18 17:01:53Z

Risky, 5 bytes

0?/20_?:?

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Doesn't work with the empty string; OP hasn't clarified if that's a problem.

Explanation

0 transpose ? input / split into groups of 2 2 0 reduce _ ? accumulator : = ? item

score 2 · Accepted Answer · 2022-04-07 19:13:05Z

PHP4 (45 chars)

Given $argv[1] as a command line argument :

echo preg_match('#^((.)\2)*$#',$argv[1])?1:0;

The script will output 0 or 1 to answer.

PHP7.4 (41 chars)

The $f arrow function will return the answer :

$f=fn($s)=>preg_match('#^((.)\2)*$#',$s);

C gcc (27 chars)

Function f today return an indication of whether or not the input is double speak :

f(char*s){1[s]-*s||f(s+2);}

Usage :

#include <stdio.h> int main() { printf("EXPECT %5s ... %-5s .. aba\n","NO", f("aba")?"NO":"YES"); printf("EXPECT %5s ... %-5s .. abba\n","NO", f("abba")?"NO":"YES"); printf("EXPECT %5s ... %-5s .. aabb\n","YES", f("aabb")?"NO":"YES"); printf("EXPECT %5s ... %-5s .. aaabb\n","NO", f("aaabb")?"NO":"YES"); printf("EXPECT %5s ... %-5s .. tthhiiss\n","YES", f("tthhiiss")?"NO":"YES"); printf("EXPECT %5s ... %-5s .. ttthhhiiisss\n","NO", f("ttthhhiiisss")?"NO":"YES"); }

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C Variants :

g(char*s){s=*s&&g(s+2)+s[1]-*s;} // 32 chars h(char*s){return*s&&h(s+2)+s[1]-*s;} // 36 chars

chunes · Accepted Answer · 2023-06-02 03:03:35Z

2

><> (Fish), 22 bytes

l2%?v>l?v1n; ;n0<^?=<

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answered Jun 2, 2023 at 3:03

chunes

27.8k3 gold badges32 silver badges55 bronze badges

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Noah · Accepted Answer · 2023-09-29 00:30:06Z

X86_64/Linux Machine Code, 19-Bytes

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Usage:

$> gcc -Wl,-Tbss=0x80000000 -DIDEAL_BSS -s -static -nostartfiles -nodefaultlibs -nostdlib -Wl,--build-id=none double-speak.S -o double-speak $> echo -n "<input> | ./double-speak; echo $?

Program reads input from stdin (it is sensitive to the exact byte count of input, i.e stray spaces/new lines will change result).

Returns 0 for double-speak, and non-zero otherwise.

Notes:

Size is measured in machine code (i.e 19 bytes of PROGBITS; .text, .data, etc...)
The 19-byte size assumes the above compile command which sets the BSS address at an ideal value. With generic compile commands (no linker inputs), its 21-bytes.

Program:

/* Uncomment below if BSS was setup at 2^20. */ /* #define IDEAL_BSS */ .global _start .text _start: /* Incoming registers are zero. */ decl %edx #ifdef IDEAL_BSS btsl %edx, %esi #else movl $G_mem, %esi #endif /* eax == 0 == SYS_read. */ /* edi == 0 == STDIN. */ syscall xchgl %eax, %ecx loop: /* Load next pair. */ lodsw /* Need to decr by 2 each loop. */ decl %ecx /* Check that bytes match. */ xorb %ah, %al /* Break if ne or end of count. */ loope loop /* edi is zero (clears hi bits of eax). eax is zero if double- speak. Otherwise non-zero. */ xchgl %eax, %edi /* Exit. */ movb $60, %al syscall .section .bss G_mem: .space(4096 * 8)

Example/Test:

$> for x in aba abba aabb aaabb tthhiiss ttthhhiiisss; do echo -n "${x}" | ./double-speak; echo "${x} -> $?"; done aba -> 3 abba -> 3 aabb -> 0 aaabb -> 3 tthhiiss -> 0 ttthhhiiisss -> 28

noodle person · Accepted Answer · 2023-09-29 01:07:52Z

TypeScript's Type System, 86 bytes

type F<S>=S extends`${infer C}${infer D}${infer R}`?C extends D?F<R>:0:S extends""?1:0

Try it at the TypeScript playground!

This is a generic type F taking a string-literal type parameter S, and outputting 0 for non-double-speak and 1 for double-speak.

None of the test cases offer a case where all of the pairs are equal but the whole string is of odd length, which tripped me up a bit. This is likely golfable, maybe that last extends clause can be dropped with something clever.

Explanation:

type F<S> = // Match S to extract the first two chars C and D and the rest R S extends `${infer C}${infer D}${infer R}` // if it matched: is C the same type as D? ? C extends D ? F<R> // if so, recurse with R : 0 // otherwise, it's not double-speak; return 0 // if it didn't match, we check if the string is empty or has one character. : S extends "" ? 1 : 0

noodle person · Accepted Answer · 2023-09-29 01:48:53Z

JavaScript (Node.js), 26 bytes

f=([a,b,...c])=>a==b&&f(c)

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Outputs via exit-code. I think this is really nice and clean but that's just my opinion. Unfortunately, this doesn't beat the tried-and-true regex.

Explanation:

f=([a,b,...c])=>...

Makes a function f that destructures its string argument into the first character a, the second character b, and rest of the string c.
a==b&&f(c)

Check if a is equal to b. The && (AND) operator only evaluates its right argument if its left is true, so if it is true we recurse with c.

If a and b aren't equal, then it can't be double speak, so we stop recursion to output with a 0 exit code.

If they're equal, we keep checking the next two until either
- A) recursion stops because a isn't equal to b, or
- B) a and b are both undefined because we've reached the end of the string and there are no more characters left, so we recurse until the recursion depth is hit, giving an exit code of 1.

manatwork · Accepted Answer · 2019-08-07 08:43:21Z

Gema, 17 characters

?$1= ?=0@end \Z=1

Outputs 1 on double speak and 0 on not.

Sample run:

bash-5.0$ echo -n 'TThhiiss iiss ddoouubbllee ssppeeaakk!!' | gema '?$1=;?=0@end;\Z=1' 1

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Gema, 12 characters

?$1= ?=@fail

Terminates with exit code 0 on double speak and 2 on not.

Sample run:

bash-5.0$ echo -n 'TThhiiss iiss ddoouubbllee ssppeeaakk!!' | gema '?$1=;?=@fail' bash-5.0$ echo $? 0

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Quinn · Accepted Answer · 2019-08-07 12:51:38Z

Kotlin, 59 57 bytes

{s->(0..s.length-1 step 2).fold(""){t,c->t+s[c]+s[c]}==s}

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-1 byte thanks to Khuldraeseth na'Barya

-1 byte changing it -> s

Slightly lazy attempt - basically just took my answer from the doublespeak question, applied it to every second char of the input and see if the result is the input.

@Khuldraesethna'Barya updated, thanks! did not know that was a thing — Quinn
– Quinn, Commented Aug 6, 2019 at 19:32

Brojowski · Accepted Answer · 2019-08-07 21:03:51Z

1

Kotlin, 4649 bytes

-3 bytes thanks to @cubic lettuce

{it.chunked(2).all{it.length>1&&it[0]==it[1]}}

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{it.length%2==0&&it.chunked(2).all{it[0]==it[1]}}

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edited Aug 7, 2019 at 21:03

answered Aug 7, 2019 at 18:44

Brojowski

1615 bronze badges

1

\$\begingroup\$ Save 3 bytes by {it.chunked(2).all{it.length>1&&it[0]==it[1]}} ;) \$\endgroup\$

cubic lettuce
– cubic lettuce

2019-08-07 20:41:01 +00:00
Commented Aug 7, 2019 at 20:41

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Loki · Accepted Answer · 2019-08-08 04:52:39Z

1

C (tcc), 59 55 50 bytes

f(char *s){while(*s==*++s)s++;return!*--s&&s!="";}

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Thanks to Jo King for the 4 bytes and Unrelated String for saving 5 bytes

Can it be even shorter?

edited Aug 8, 2019 at 4:52

answered Aug 7, 2019 at 11:10

Loki

312 bronze badges

\$\begingroup\$ *s==*++s, how is this not UB when *s points to the end of the string? \$\endgroup\$

Taemyr
– Taemyr

2019-08-07 11:26:33 +00:00
Commented Aug 7, 2019 at 11:26
\$\begingroup\$ the *s will always point to the last character of the string given in argument which is not last character because string here ends with '\0' so the *++s gets the \0 \$\endgroup\$

Loki
– Loki

2019-08-07 11:36:00 +00:00
Commented Aug 7, 2019 at 11:36
1

\$\begingroup\$ You increment s by two each time through the loop, so if there is an even number of actuall characters in the string I do not see how you can guarantee that *s never points to the '\0' \$\endgroup\$

Taemyr
– Taemyr

2019-08-07 11:58:43 +00:00
Commented Aug 7, 2019 at 11:58
\$\begingroup\$ You could golf it considerably by replacing *--s=='\0' with the simple !*--s, but also note that most challenges require submissions to be either functions or full programs, and this is neither. \$\endgroup\$

Unrelated String
– Unrelated String

2019-08-07 19:37:15 +00:00
Commented Aug 7, 2019 at 19:37
\$\begingroup\$ Thanks guys for helping shortening it and @Taemyr play with this code TIO I don't need to care if *s gets the \0 character cause then the *++s will get the first character from the string used in printf. \$\endgroup\$

Loki
– Loki

2019-08-08 05:07:13 +00:00
Commented Aug 8, 2019 at 5:07

| Show 3 more comments

Berry M. · Accepted Answer · 2019-08-08 15:14:19Z

Rust, 73 bytes

|s:&str|!s.chars().enumerate().any(|(i,c)|s.chars().nth(i|1).unwrap()!=c)

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Community · Accepted Answer · 2020-06-17 09:04:33Z

T-SQL 2012, 76 bytes

Looping using the following logic.

Finding the first match on the first character in the rest of the string.

If the match is on the second position, the first 2 characters are removed.

if the match is on a later position, character 0 to 1 is removed, resulting in null string.

If there are no matches, characters 3-4 are removed. Repeating this will eventually result in a null string.

The final string will be an empty string or a null string.

Empty string is "double speak"(1). Null string is not "double speak"(0).

DECLARE @ varchar(max)='ccbbddeeff' WHILE @>''SET @=stuff(@,-3/~charindex(left(@,1),@,2),2,'')PRINT iif(@=0,1,0)

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kanine · Accepted Answer · 2019-08-09 04:09:05Z

1

JavaScript (Node.js), 26 bytes

s=>!s.replace(/(.)\1/g,'')

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answered Aug 9, 2019 at 4:09

kanine

2011 silver badge4 bronze badges

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Przemysław Czechowski · Accepted Answer · 2019-08-09 09:24:45Z

1

C++ (gcc), 48 47 45 43 bytes

-2 bytes thanks to @ceilingcat
-2 bytes thanks to @JoKing

recursive function assuming zero terminated char table

int f(char*s){return!*s||*s==s[1]&&f(s+2);}

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edited Aug 9, 2019 at 9:24

answered Aug 8, 2019 at 17:21

Przemysław Czechowski

1214 bronze badges

\$\begingroup\$ @ceilingcat cool, I didn't now you can be that concise \$\endgroup\$

Przemysław Czechowski
– Przemysław Czechowski

2019-08-09 08:02:18 +00:00
Commented Aug 9, 2019 at 8:02
\$\begingroup\$ @JoKing it works, there's just a warning because I'm using string literals to generate right kind of input - zero-terminated char* - which is not exactly legal in c++ but gcc allows it \$\endgroup\$

Przemysław Czechowski
– Przemysław Czechowski

2019-08-09 08:26:28 +00:00
Commented Aug 9, 2019 at 8:26
\$\begingroup\$ Ah sorry, I thought the lack of output meant it wasn't working. 43 bytes \$\endgroup\$

Jo King
– Jo King

2019-08-09 08:36:41 +00:00
Commented Aug 9, 2019 at 8:36

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Grzegorz Oledzki · Accepted Answer · 2019-08-09 19:05:41Z

1

EDIT:

This solution is totally broken as demonstrated by the aabbbb test case. Thanks to @manatwork for pointing this out. Do not pass Go! Do not collect 200 dollars!

Bash and Gnu utils, 46 45 bytes

fold -1|uniq -c|grep -qv "2 "&&echo 0||echo 1

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-1 byte by skipping the first space in grep expression

edited Aug 9, 2019 at 19:05

answered Aug 8, 2019 at 18:47

Grzegorz Oledzki

2431 silver badge7 bronze badges

\$\begingroup\$ Not sure if I can use grep exit codes and return output there? Instead of this &&echo 0||echo1 \$\endgroup\$

Grzegorz Oledzki
– Grzegorz Oledzki

2019-08-09 09:32:48 +00:00
Commented Aug 9, 2019 at 9:32
1

\$\begingroup\$ This works fine on the question's test cases, but as I understand the challenge, it should output 1 on Khuldraeseth na'Barya's suggested test case, “aabbbb”. \$\endgroup\$

manatwork
– manatwork

2019-08-09 09:34:19 +00:00
Commented Aug 9, 2019 at 9:34
\$\begingroup\$ @manatwork You're right. This solution is buggy in that sense. \$\endgroup\$

Grzegorz Oledzki
– Grzegorz Oledzki

2019-08-09 11:23:12 +00:00
Commented Aug 9, 2019 at 11:23

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val - disappointed in SE · Accepted Answer · 2019-08-09 21:58:52Z

Lua, 90 87 86 82 bytes

a,e=1,os.exit;(...):gsub('.',load's=...a=a~=1 and(a==s and 1 or e(1))or s')e(a==1)

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Take input as argument, use exit code as output.

Explanation

This is based on abusing few Lua features:

os.exit could accept either number, allowing short code for exit or boolean, making last check possible (true meaning success, false meaning failure).
gsub can be also used to iterate over string in callback-style, not only for doing replacement.
load is shorter than function(...) end.
... is often shorter than arg[1].

Whole idea hidden behind those tricks:

For each character: either remember if nothing is already it or perform check: if current is different from remembered, fail. Otherwise, reset remembered value and continue.
When done, make sure that there's nothing pending in the buffer (e(a==1)). This is required to fail on strings with odd length.

Ver Nick · Accepted Answer · 2019-08-11 17:13:13Z

1

C++ (gcc), 156 145 bytes

#include <iostream> int f(){ char a[2]; while(std::cin.get(a, 3)) if(a[0] != a[1]) return 0; return 1; } int main() { std::cout << f(); }

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edited Aug 11, 2019 at 17:13

answered Aug 11, 2019 at 9:49

Ver Nick

6076 silver badges17 bronze badges

\$\begingroup\$ Welcome to the site! C++ is pretty lenient about whitespace so you can save bytes by removing a bunch of it. \$\endgroup\$

Wheat Wizard
– Wheat Wizard ♦

2019-08-11 11:58:56 +00:00
Commented Aug 11, 2019 at 11:58
\$\begingroup\$ @SriotchilismO'Zaic Thank you! \$\endgroup\$

Ver Nick
– Ver Nick

2019-08-11 17:12:14 +00:00
Commented Aug 11, 2019 at 17:12

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Is it double speak?

102 Answers 102

Kotlin, 56 52 bytes

C (gcc), 50 bytes

C (gcc), 38 bytes

Pip, 31 bytes

Perl 6, 14 bytes

PHP, 51 50 38 bytes

PHP, 37 40 bytes

PHP, 55 bytes

Java (JDK), 64 bytes

Explanations

Stax, 6 5 bytes

Unpacked (6 bytes) and explanation

Pushy, 13 bytes

naz, 50 bytes

Burlesque, 8 bytes

Burlesque, 11 bytes

Marbelous, 84 bytes

JavaScript (Node.js), 23 bytes

Risky, 5 bytes

Explanation

PHP4 (45 chars)

PHP7.4 (41 chars)

C gcc (27 chars)

><> (Fish), 22 bytes

X86_64/Linux Machine Code, 19-Bytes

TypeScript's Type System, 86 bytes

JavaScript (Node.js), 26 bytes

Gema, 17 characters

Gema, 12 characters

Kotlin, 59 57 bytes

Kotlin, 4649 bytes

C (tcc), 59 55 50 bytes

Rust, 73 bytes

T-SQL 2012, 76 bytes

JavaScript (Node.js), 26 bytes

C++ (gcc), 48 47 45 43 bytes

EDIT:

Bash and Gnu utils, 46 45 bytes

Lua, 90 87 86 82 bytes

Explanation

C++ (gcc), 156 145 bytes

Linked

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