use strict;
use warnings;

while ( my $line = <DATA> ) {
	print +( join ',', map "($_)", $line =~ /(\d*,\d*),?/g ), "\n";
}

__DATA__
1,1,,,,
1,2,,,,
3,4,1,1,,
1,1,1,1,,
5,6,3,4,1,2
1,1,1,1,1,1
,,,,1,1
,,1,2,,
,,1,1,1,2
,,,,,
5,6,3,4,2,2