#!perl -l

@strings = <DATA>;

for(@strings)
{
	chomp;
	s/,/'}{'/g;
	s/^/\$hash{'/;
	s/$/'}++/;
	print "eval $_";
	eval $_;
}

use Data::Dumper;
print Dumper \%hash;

__DATA__
string1,string2,string3,string4
string3,string4
string1,string2,string3