local $/ = "Startpoint"; $temp="abc";
 while(<INFILE1>){ 

 /[(](\w+)[^(]+[(](\w+)[^:]+:\s+(\w+).*?slack[^-]+(-\S+)/s; 
       
 $PG{$3}{"$1-$2"}{"$cou"} = $4; 
 $cou++;
 }

##</code><code>##

my %PG;
my $cou = 0;

local $/ = 'Startpoint';
RECORD:
while (<INFILE1>) { 

    next RECORD unless  # unless valid data extracted from record
        /[(](\w+)[^(]+[(](\w+)[^:]+:\s+(\w+).*?slack[^-]+(-\S+)/s; 
       
    $PG{$3}{"$1-$2"}{$cou} = $4; 
    $cou++;
    
    }


##</code><code>##

--------------undefined key of my hash---------------
  '' => {
                   '-' => {
                            '' => undef
                          }
                 },