$VAR1 = [
          'AB',
          '1',
          'Traverse'
        ];
$VAR2 = [
          'AB',
          '3',
          'Traverse'
        ];
$VAR3 = [
          'CD',
          '2',
          'Traverse'
        ];
$VAR4 = [
           'CD',
           '2',
           'Traverse'
         ];

$VAR1 = [
          'JK',
          '1',
          'Traverse1'
        ];
$VAR2 = [
          'JK',
          '3',
          'Traverse1'
        ];
$VAR3 = [
          'KJ',
          '2',
          'Traverse1'
        ];
$VAR4 = [
           'KJ',
           '2',
           'Traverse1'
         ];

##</code><code>##

Traverse
AB		4 
CD		4
Subtotal	8

Traverse1
JK		4 
KJ		4
Subtotal	8

Total		16

##</code><code>##

my $size = scalar(@f);
for ( my $i=0;$i<$size;$i++ ) {
my $key = "$f[$i]->[0]";
$result{$key}->[0] += $f[$i]->[1]; 
}

##</code><code>##

Traverse
AB		4 
CD		4
Subtotal	8

Traverse1
JK		4 
KJ		4
Subtotal	8

Total		16