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Perl and string array problem


 
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# 1  
Old 07-01-2010
Perl and string array problem

Code:
#!/usr/bin/perl
my @arr=("hello", "how", "are", "you");
$l=length(@arr);
print $l;

This print 1.Why?
How can i print the array size = 4?
I want to store these in an array.
Code:
hello
how 
are
you

And then i want to access these element through indexing.
How can i do this?
# 2  
Old 07-01-2010
Code:
print $#arr+1;

$#arr contains index of array's last element.
This User Gave Thanks to bartus11 For This Post:
# 3  
Old 07-01-2010
Quote:
% perldoc -f length
length EXPR
length Returns the length in characters of the value of EXPR. If EXPR
is omitted, returns length of $_. Note that this cannot be
used on an entire array or hash to find out how many elements
these have. For that, use "scalar @array" and "scalar keys
%hash" respectively.
Code:
% perl -le'
  my @arr = qw(hello how are you);
  $l = @arr;
  print $l;
  '
4

This User Gave Thanks to radoulov For This Post:
# 4  
Old 07-01-2010
Quote:
Originally Posted by cola
And then i want to access these element through indexing.
How can i do this?
Code:
print $arr[1]; #prints how
print $arr[3]; #prints you

# 5  
Old 07-01-2010
Quote:
Originally Posted by radoulov
Code:
% perl -le'
  my @arr = qw(hello how are you);
  $l = @arr;
  print $l;
  '
4

I just knew about
Code:
$k=$#(@arr);

But $l=@arr even looks easier.

Done.

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