The idea is to look for spaces on word boundaries and remove them (i.e it monitors the transition of a word character into a non-word character and then removes the non-word character), you can also monitor the transition of a non-word character into a word character by detecting the word character boundary post a non-word character as in the second line. 

$string = "H e l l o  P e r l p r i n t";
print $string for $string =~ s/\b[ ]//g; 
print $string for $string =~ s/[ ]\b//g;


UPDATE:added non-capturing square brackets to account for more efficie
+ncy after
 Anomalous Monk's enlightenment...

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An exercise question for you, what do you think the reason that running both the print lines above together would result in the following output, But running only a single line of either the two print statements works just fine?! 
Hello PerlprintHelloPerlprint

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Excellence is an Endeavor of Persistence. Chance Favors a Prepared Mind.

In reply to Re: help me ---regarding string by biohisham
in thread help me ---regarding string by perlprint

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