The main problem I see is that you are using the literal character 'd' in your regexes, where you want \d. "d" matches only the character "d", whereas "\d" matches the digits 0-9. So, for example, this: 

if($arr[$i]=~/^d+$/){

[download]

Should be 

if($arr[$i]=~/^\d+$/){

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(Although as a matter of style, I would probably rewrite the whole loop as follows:) 

for( @arr ) { 
  # if the element contains only digits
    if( /^\d+$/ ) { 
      $_ /= 2;
    }
}

[download]

In reply to Re: wisdom needed for string matching and array processing by friedo
in thread wisdom needed for string matching and array processing by sierrastar

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