Array length

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Revision as of 20:04, 27 September 2015 by rosettacode>Paddy3118 (Promote from draft to full task status.)
Task
Array length
You are encouraged to solve this task according to the task description, using any language you may know.

Determine the amount of elements in an array.
As an example use an array holding the strings 'apple' and 'orange'.

See also

ALGOL 68

<lang algol68># UPB returns the upper bound of an array, LWB the lower bound # []STRING fruits = ( "apple", "orange" ); print( ( ( UPB fruits - LWB fruits ) + 1, newline ) ) # prints 2 #</lang>

EchoLisp

<lang scheme> (length '("apple" "orange")) ;; list

  → 2

(vector-length #("apple" "orange")) ;; vector

  → 2

</lang>

Haskell

<lang Haskell>-- Char -> Int length ["apple", "orange"]</lang>

JavaScript

<lang javascript>console.log(['apple', 'orange'].length);</lang>

ooRexx

<lang oorexx> /* REXX */ a = .array~of('apple','orange') say a~size 'elements' Do e over a

 say e
 End

Say "a[2]="a[2]</lang>

Output:
2 elements
apple
orange
a[2]=orange

PHP

<lang php>print count(['apple', 'orange']); // Returns 2</lang>

Python

<lang python>>>> print(len(['apple', 'orange'])) 2 >>> </lang>

REXX

<lang rexx>/* REXX ----------------------------------------------

  • The compond variable a. implements an array
  • By convention, a.0 contains the number of elements
  • ---------------------------------------------------*/

a.=0 /* initialize the "array" */ call store 'apple' Call store 'orange' Say 'There are' a.0 'elements in the array:' Do i=1 To a.0

 Say 'Element' i':' a.i
 End

Exit store: Procedure Expose a. z=a.0+1 a.z=arg(1) a.0=z Return</lang>

Output:
There are 2 elements in the array:
Element 1: apple
Element 2: orange

SQL

<lang sql>SELECT COUNT() FROM (VALUES ('apple'),('orange'));</lang>

zkl

zkl doesn't support arrays natively, use lists instead. <lang zkl>List("apple", "orange").len().println() //-->2, == L("apple", "orange") T("apple", "orange").len().println() //-->2, read only list (ROList) </lang>