# File:	searchAllsub.pl
# Title: 	Given string and a character (pattern)
#			Capture all the positions of the character in string
#           use system function: pos($seq) - gives next position
# C:\myPerl>perl searchAllsub.pl
#   There are 3 positions where a is found in mathematica
### 		Find positions for a in mathematica    ***
$seq = 'mathematica';		
$regex = 'a';    	#search a in mathematica
@Places = searchAll($seq,$regex);	#call subroutine
$Places = @Places;					# find length array result
print "\nThere are ", $Places, " positions where $regex is found in $seq: ", @Places;
exit;

### Subroutine, takes 2 args: sequence and a charcater and return list of positions ###
sub searchAll {
	my @Positions = ();			   # initialize array where you put positions
	my ($s,$r) = @_;               # array of arguments from main program: sequence and character
	while ( $s =~ m/$r/g ) 	{      # search globally (g) pattern $r is $s 
		push (@Positions,(pos($s)-1));	# decrement because pos() gives next position
	}
	return @Positions;
}