Hi Corion,
I have already given required input and output. See the below code what i am trying to do? I need to identify years in a line and it may come like 2005, 2005a, a2005, May 31, 2005 some thing like that. Here first i am trying to find the occurance.
I need the below output:
1. i need to find out the words which has 4 digits number. it's my first requirement.
2. then i should collect all years and needs to find before/after two words due to full date appearances. 

$var='Hobbs, F. 2005a. Examining American Household Composition: b1990
+ and 2000. U.S. Census Bureau, Census 2000 Special Reports, CENSR-24.
+ I.S. Government Printing Office, Washington, DC.';

#$var=~s/(\w?) (\w?) ([0-9]{4}+[a-zA-Z]?) (\w?) (\w?)/&identify_year($
+1.$2.$3.$4.$5)/ge;

$var=~s/([0-9]{4})/&identify_year($1)/ge;

sub identify_year
{
  my ($input)=@_;

  print "$input\n";
  return ($input);
}

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In reply to Re^2: find one by one occurances by Selvakumar
in thread find one by one occurances by Selvakumar

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