problemas com array

pessoal gostaria de uma ajuda para colocar em uma array as variaveis extra1,extra2,extra3,extra4 e mostra uma soma no final.

if ($feriado=="N" and $diasemana!="Sábado" and $diasemana!="Domingo"){
$extra1 = $hora_ponto.":".$min_ponto.":".$secs_ponto + $hora_ponto1.":".$min_ponto1.":".$secs_ponto1 - "08:00:00";
?>
<table border="1">
<tr>
<td><strong>Data: </strong></td>
<td><strong>Dia da Semana:</strong></td>
<td><strong>Hora Entrada: </strong></td>
<td><strong>Hora Saida Almoço: </strong></td>
<td><strong>Hora Volta Almoço:</strong></td>
<td><strong>Hora Saida:</strong></td>
<td><strong>Total Geral:</strong></td>
<td><strong>Total Extras: </strong></td>
<td><strong>Feriado:</strong></td>
</tr>
<tr>
<td><?php print "$dia/$mes/$ano";?> </td>
<td><?php print $diasemana;?></td>
<td><?php print $entr_manha;?> </td>
<td><?php print $saida_manha;?> </td>
<td><?php print $entr_tarde;?> </td>
<td><?php print $saida_tarde;?> </td>
<td><?php print $hora_ponto.":".$min_ponto.":".$secs_ponto + $hora_ponto1.":".$min_ponto1.":".$secs_ponto1;?></td>
<td><?php print @$extra1;?></td>
<td><?php print $feriado?></td>
</tr>
</table>
<?php
}
if ($feriado=="S" and $diasemana!="Sábado" and $diasemana!="Domingo"){
$hora = 1;
$extra2 = ($hora_ponto.":".$min_ponto.":".$secs_ponto + $hora_ponto1.":".$min_ponto1.":".$secs_ponto1) * $hora;
?>
<table border="1">
<tr>
<td><strong>Data: </strong></td>
<td><strong>Dia da Semana:</strong></td>
<td><strong>Hora Entrada: </strong></td>
<td><strong>Hora Saida Almoço: </strong></td>
<td><strong>Hora Volta Almoço:</strong></td>
<td><strong>Hora Saida:</strong></td>
<td><strong>Total Geral:</strong></td>
<td><strong>Total Extras: </strong></td>
<td><strong>Feriado:</strong></td>
</tr>
<tr>
<td><?php print "$dia/$mes/$ano";?> </td>
<td><?php print $diasemana;?></td>
<td><?php print $entr_manha;?> </td>
<td><?php print $saida_manha;?> </td>
<td><?php print $entr_tarde;?> </td>
<td><?php print $saida_tarde;?> </td>
<td><?php print $hora_ponto.":".$min_ponto.":".$secs_ponto + $hora_ponto1.":".$min_ponto1.":".$secs_ponto1;?></td>
<td><?php print @$extra2;?></td>
<td><?php print $feriado?></td>
</tr>
</table>
<?php
}
if ($diasemana=="Sábado"){
$hora = 1;
$extra3 = ($hora_ponto.":".$min_ponto.":".$secs_ponto + $hora_ponto1.":".$min_ponto1.":".$secs_ponto1) * $hora;
?>
<table border="1">
<tr>
<td><strong>Data: </strong></td>
<td><strong>Dia da Semana:</strong></td>
<td><strong>Hora Entrada: </strong></td>
<td><strong>Hora Saida Almoço: </strong></td>
<td><strong>Hora Volta Almoço:</strong></td>
<td><strong>Hora Saida:</strong></td>
<td><strong>Total Geral:</strong></td>
<td><strong>Total Extras: </strong></td>
<td><strong>Feriado:</strong></td>
</tr>
<tr>
<td><?php print "$dia/$mes/$ano";?> </td>
<td><?php print $diasemana;?></td>
<td><?php print $entr_manha;?> </td>
<td><?php print $saida_manha;?> </td>
<td><?php print $entr_tarde;?> </td>
<td><?php print $saida_tarde;?> </td>
<td><?php print $hora_ponto.":".$min_ponto.":".$secs_ponto + $hora_ponto1.":".$min_ponto1.":".$secs_ponto1;?></td>
<td><?php print @$extra3;?></td>
<td><?php print $feriado?></td>
</tr>
</table>
<?php
}
if ($diasemana=="Domingo"){
$hora = 1;
$extra4 = ($hora_ponto.":".$min_ponto.":".$secs_ponto + $hora_ponto1.":".$min_ponto1.":".$secs_ponto1) * $hora;
?>
<table border="1">
<tr>
<td><strong>Data: </strong></td>
<td><strong>Dia da Semana:</strong></td>
<td><strong>Hora Entrada: </strong></td>
<td><strong>Hora Saida Almoço: </strong></td>
<td><strong>Hora Volta Almoço:</strong></td>
<td><strong>Hora Saida:</strong></td>
<td><strong>Total Geral:</strong></td>
<td><strong>Total Extras: </strong></td>
<td><strong>Feriado:</strong></td>
</tr>
<tr>
<td><?php print "$dia/$mes/$ano";?> </td>
<td><?php print $diasemana;?></td>
<td><?php print $entr_manha;?> </td>
<td><?php print $saida_manha;?> </td>
<td><?php print $entr_tarde;?> </td>
<td><?php print $saida_tarde;?> </td>
<td><?php print $hora_ponto.":".$min_ponto.":".$secs_ponto + $hora_ponto1.":".$min_ponto1.":".$secs_ponto1;?></td>
<td><?php print @$extra4;?></td>
<td><?php print $feriado?></td>
</tr>
</table>
<?php
}
}
?>