Determine whether strings are anagrams

Question

Challenge

Given two strings, work out if they both have exactly the same characters in them.

Example

Input

word, wrdo

This returns true because they are the same but just scrambled.

Input

word, wwro

This returns false.

Input

boat, toba

This returns true

Rules

Here are the rules!

• Assume input will be at least 1 char long, and no longer than 8 chars.
• No special characters, only a–z
• All inputs can be assumed to be lowercase

Test Cases

boat, boat = true
toab, boat = true
oabt, toab = true
a, aa = false
zzz, zzzzzzzz = false
zyyyzzzz, yyzzzzzy = true
sleepy, pyels = false
p,p = true

Answer 1

Python, 32 bytes

f=lambda a,b,S=sorted:S(a)==S(b)

Answer 2

Golfscript, 3 chars?

$$=

usage:

'boat'$'baot'$=
1

'toab'$'boat'$=
1

'oabt'$'toab'$=
1

'a'$'aa'$=
0

'zzz'$'zzzzzzzz'$=
0

'zyyyzzzz'$'yyzzzzzy'$=
1

'sleepy'$'pyels'$=
0

'p'$'p'$=
1

Answer 3

J, 8

-:&(/:~)

Literaly, match (-:) on (&) sort up (/:~)

Sample use:

   'boat' -:&(/:~) 'boat'
1
   'toab' -:&(/:~) 'boat'
1
   'oabt' -:&(/:~) 'toab'
1
   'a' -:&(/:~) 'aa'
0
   'zzz' -:&(/:~) 'zzzzzzzz'
0
   'zyyyzzzz' -:&(/:~) 'yyzzzzzy'
1
   'sleepy' -:&(/:~) 'pyels'
0
   'p' -:&(/:~) 'p'
1

Where do the 64-bit integers come into play?

Answer 4

Javascript, 192 157 152 147 125 bytes

Ok some of these languages are a lot more flexibile than I thought! Anyway this is the longer way I guess, but a different technique at least.

Compressed

Thanks to Peter and David for squeezing more chars out!

for(a=[j=p=2];j<123;)a[j]?p%a[++j]<1&&p++&&(j=0):(a[j]=p,j=0);function b(c,i){return c[i=i||0]?a[c.charCodeAt(i)]*b(c,++i):1}

Then do:

alert(b("hello")==b("elloh"));

Expanded Code

The compressed has had lots of changes, but this is the basic theory:

// Define dictionary of primes
a = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101];

// Returns the unique ID of the word (order irrelevant)
function b(c) {
    r = 1;
    for (i = 0; i < c.length; i++)
        r *= a[c[i].charCodeAt(0) - 97];
    return r
}

alert(b("hello") == b("hlleo"));

Answer 5

Golfscript, 8 bytes

This defines a function called A

{$\$=}:A

Test cases

;
'boat' 'boat' A
'toab' 'boat' A
'oabt' 'toab' A
'a' 'aa' A
'zzz' 'zzzzzzzz' A
'zyyyzzzz' 'yyzzzzzy' A
'sleepy' 'pyels' A
'p' 'p' A

Answer 6

Haskell, 31 bytes

function - 31

import List
f=(.sort).(==).sort

program - 81 58 55

import List
g=sort`fmap`getLine
main=(`fmap`g).(==)=<<g

Usage:

$ runghc anagram.hs
boat
boat
True
$ runghc anagram.hs
toab
boat
True
$ runghc anagram.hs
a
aa
False

Kudos to lambdabot and its pointfree refactoring.

Answer 7

C#, 129 chars

namespace System.Linq{class X{static void Main(string[]a){Console.Write(a[0].OrderBy(_=>_).SequenceEqual(a[1].OrderBy(_=>_)));}}}

Readable:

namespace System.Linq
{
    class X
    {
        static void Main(string[] a)
        {
            Console.Write(a[0].OrderBy(_ => _)
                  .SequenceEqual(a[1].OrderBy(_ => _)));
        }
    }
}

Answer 8

Ruby, 34 bytes

Using the IO scheme of Peter Taylors Perl solution:

p gets.chars.sort==gets.chars.sort

Answer 9

C program, 118

t[52],i;main(c){for(;i<52;)(c=getchar())<11?i+=26:t[i+c-97]++;
for(i=27;--i&&t[i-1]==t[i+25];);puts(i?"false":"true");}

Answer 10

Perl, 58 bytes

(complete program, unlike the other Perl answer which is only a function)

($c,$d)=map{[sort split//]}<>;print"@$c"eq"@$d"?true:false

49 as a function

sub f{($c,$d)=map{[sort split//]}<>;"@$c"eq"@$d"}

Answer 11

Clojure - 23 chars

As an anonymous function:

#(apply = (map sort %))

Test case example:

(#(apply = (map sort %)) ["boat" "boat"])
=> true

Answer 12

JavaScript

Based on @zzzzBov's solution.

Comparison, 65 chars (40 without function)

function f(a,b){return a.split('').sort()==b.split('').sort()+""}

Comparator, 43 chars

function f(a){return a.split('').sort()+""}

Answer 13

C++ (104 non-ws chars)

Based on counting sort. Note: Assumes strings of the same length, which seems to be implied (though not stated) by the question.

int u[123], i;

int a(char **c) {
    for(; c[0][i]; ) {
        u[c[0][i]]++;
        u[c[1][i++]]--;
    }

    i=123;
    while(i && !u[--i]);
    return !i;
}

Answer 14

APL, 2 chars

≡⍦

This is the Multiset Match function from Nars2000, one of the leading-edge APL implementations. When applied to strings, it computes exactly the function required:

      'elvis' ≡⍦ 'lives'
1
      'alec guinness' ≡⍦ 'genuine class'
1

Answer 15

R, 54 bytes

function(x,y,`~`=sort,`+`=utf8ToInt)identical(~+x,~+y)

Try it online!

Answer 16

05AB1E, 6 4 bytes

{I{Q

Try it online!

This took a while because of input difficulties. Golfed down due to pop.

Explanation:

{I{Q    Original code

{       Takes first input e.g. word and sorts -> 'dorw'
 I      Takes second input e.g. 'wrdo'
  {     Sorts second input -> 'dorw'
   Q    Compare if sorted 1 = sorted 2, then print result. 'dorw' = 'dorw', so prints 1.

Answer 17

Knight, 112 bytes

;=dF;C=mB;=a 123W<96=a-a 1Id=d!E+"a"aE++"=a"a" 0";=w"+1a";C=lB;=bP:Wb;E++"=a"Ab+wAb=bGb 1Lb;=w"+~1a";Cl;=dT;CmOd

Try it online!

Knight doesn't have arrays. It does have strings, but it only allows a subset of valid ASCII character codes. So I emulated an array by constructing strings that looks like "=a{charcode} 0" and evaling it.

Knight also has blocks. A block works like a niladic function, which can change its behavior depending on global variables. This code uses two blocks: m loops over all 26 variables a97 - a122 initializing or testing something, and l handles the part of taking input and iterating over its chars to count occurrences.

; = d F                  d = False
; C = m B                define and run block m:
  ; = a 123                a = 123
  : W < 96 = a - a 1       while 96 < (a = a - 1):
    I d                      if d:
      = d ! E + "a" a          d = ! eval("a" + a)
      E + + "=a" a " 0"      else: eval("=a" + a + " 0") (aNN = 0)
                         i.e. d is false on start, so initialize all of a97..a122 to 0
; = w "+1a"              w = "+1a" (which is necessary to run l)
; C = l B                define and run block l:
  ; = b P                  b = one line of input
  : W b                    while b is not empty:
    ; E +                    eval(concatenation of
          + "=a" A b           "=aNN"
          + w A b              w+"NN") (aNN = 1 + aNN)
                             (w = "+~1a" changes this to aNN = -1 + aNN)
    : = b G b 1 L b          b = b[1:length(b)]
                         i.e. count occurrences of chars in the first line
; = w "+~1a"             w = "+~1a"
; C l                    run block l i.e. count negative occurrences in the second line
; = d T                  d = True
; C m                    run block m
                         for each of a122..a97, check if aNN is zero
                         if true, keep checking; otherwise do useless thing
: O d                    print d

Answer 18

PHP (command line, 87 characters)

function d($s){
    return array_count_values(str_split($s));
}

echo d($argv[1]) == d($argv[2]);

Answer 19

Javascript

A (very) slightly shorter version of @zzzzBov's solution, that uses .join() instead of String boxing:

function a(b,c){return b.split('').sort().join()==c.split('').sort().join()}
alert(a('abc','bca')); //true

Similarly:

function a(b){return b.split('').sort().join()}
alert(a('abc')==a('bca')); //true

Answer 20

Clojure REPL 41 chars

(= (sort (read-line)) (sort (read-line)))

Answer 21

Java

(everyone's favorite language apparently!)

173 chars:

import java.util.*;class g{public static void main(String[]p){String[]a=p[0].split(""),b=p[1].split("");Arrays.sort(a);Arrays.sort(b);System.out.print(Arrays.equals(a,b));}}

(Doesn't print newline char to save 2 chars from println)

Compile and run:

javac g.java
java -cp . g abcdef fedcba
true

Love to see a shorter one...

Answer 22

sed, 45 chars

It's even possible in my favourite - sed! Just one regular expression to solve the anagram! Just keep removing the corresponding letters:

:
s/(.)(.*,.*)\1/\2/
t
/\w/{i\false
d}
i\true

(to be invoked with -nE)

Perl, 48

1while s/(.)(.*,.*)\1/\2/;$_=/\w/?"false":"true"

To be invoked with -p.

Perl function, 39

sub f{$,while s/(.)(.*,.*)\1/\2/;!/\w/}

Answer 23

Perl, 62 bytes

This function takes the strings as arguments and returns true or false.

sub f{my@a;for$.(1,-1){$a[ord]+=$.for split//,pop}!grep{$_}@a}

Stores the ASCII values in an array and checks if it evens out. Increments for the first word and decrements for the second word.

Answer 24

Python 3, 107 97 76 64

s=sorted;a,b=input().split(', ')
print(str(s(a)==s(b)).lower())

Obviously this can be shortened if we don't take the OP's wording literally and lowercase "true" and "false"...

Answer 25

Python, 32 bytes

p=sorted
f=lambda a,b:p(a)==p(b)

Answer 26

Bash, 88 characters

diff <(grep -o .<<<$1|sort) <(grep -o .<<<$2|sort)>/dev/null && echo true || echo false

Answer 27

Scala in REPL (32)

readLine.sorted==readLine.sorted

Scala function (43)

def f(a:String,b:String)=a.sorted==b.sorted

Scala program (61)

object A extends App{println(args(0).sorted==args(1).sorted)}

These leverage a neat feature of Scala whereby a String can also be treated as a sequence of characters (Seq), with all the operations on Seq being available.

Answer 28

APL - 13 chars

{(⍺[⍋⍺])≡⍵[⍋⍵]}

Call like this:

      'boat' {(⍺[⍋⍺])≡⍵[⍋⍵]} 'baot'
1
      'baot' {(⍺[⍋⍺])≡⍵[⍋⍵]} 'boat'
1
      (,'a') {(⍺[⍋⍺])≡⍵[⍋⍵]} 'aa'
0

In the last example, 'a' represents a single character, and the prefix , will convert it into a string.

Answer 29

Java (134 bytes)

int[][]c=new int[2][26];
for(int i=0;i<2;i++)for(byte a:args[i].getBytes())c[i][a-97]++;
System.out.print(Arrays.equals(c[0],c[1]));`

This makes an array to count the number of times each letter appears, and then compares the arrays to check if they are equal.

Answer 30

Perl, 77 75 chars

The I/O of the problem aren't well specified; this reads two lines from stdin and outputs true or false to stdout.

sub p{join'',sort split'',$a}$a=<>;$x=p;$a=<>;print$x eq p()?"true":"false"

(Thanks to Tim for 77 -> 75)