my $c;
my $test="This is a test string";


for ( my $i = 0; $i < length($test); $i++ ) { 
    $c = substr( $test, $i, 1);
    print "Character #",$i," = ",$c," from string ",$test,"\n";
}

for (my $len = 1; $len <= length($test); $len++) {
	for ( my $i = 0; $i < length($test); $i++ ) { 
   	     $c = substr( $test, $i, $len);
             print "String of length ",$len, " string at ",$i," = ",$c," from string ",$test,"\n";
             }
    }