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Author Count the occurence of a character
Jaffer Shaik

2004-07-23, 8:56 am

Dear Friends,

I have the below strig

$str = "abckdweqadidkaaaaisdikda";

In the above string, I want to count the occurrences of character 'a',
i.e I should get count of a = 7.

How can i achieve this in Perl.

Thank you,
Jaffer.
Remo Sanges

2004-07-23, 8:56 am

On Jul 23, 2004, at 11:42 AM, Jaffer Shaik wrote:

> $str = "abckdweqadidkaaaaisdikda";
>
> In the above string, I want to count the occurrences of character 'a',
> i.e I should get count of a = 7.
>
> How can i achieve this in Perl.
>


@a=$str=~m/a/g;
print scalar(@a)."\n";

Remo

Paul Johnson

2004-07-23, 8:56 am

On Fri, Jul 23, 2004 at 03:12:22PM +0530, Jaffer Shaik wrote:

> I have the below strig
>
> $str = "abckdweqadidkaaaaisdikda";
>
> In the above string, I want to count the occurrences of character 'a',
> i.e I should get count of a = 7.
>
> How can i achieve this in Perl.


$count = $str =~ tr/a//;

See "Regexp Quote-Like Operators" in perldoc perlop.

--
Paul Johnson - paul@pjcj.net
http://www.pjcj.net
David Storrs

2004-07-24, 3:55 am


On Fri, Jul 23, 2004 at 12:13:48PM +0200, Paul Johnson wrote:
> On Fri, Jul 23, 2004 at 03:12:22PM +0530, Jaffer Shaik wrote:
>
>
> $count = $str =~ tr/a//;


Note that this modifiees the string. You might want to do

$count = $str =~ tr/a/a/;

instead.

--Dks

John W. Krahn

2004-07-28, 8:56 pm

David Storrs wrote:
> On Fri, Jul 23, 2004 at 12:13:48PM +0200, Paul Johnson wrote:
>
>
> Note that this modifiees the string. You might want to do
>
> $count = $str =~ tr/a/a/;
>
> instead.


They both modify the string and in fact they both do exactly the same thing.

perldoc perlop
[snip]
Otherwise, if the REPLACEMENTLIST is
shorter than the SEARCHLIST, the final character is replicated till
it is long enough. If the REPLACEMENTLIST is empty, the SEARCHLIST
is replicated. This latter is useful for counting characters in a
class or for squashing character sequences in a class.



John
--
use Perl;
program
fulfillment
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