Getting data into array - laravel

Question

I'm working on some e-commerce website based on merchant. There is problem comping in submitting order. the problem is when i'm selecting same merchant that time order will be stored successfully, but when i'm selecting multiple product from different merchant that time my function through error of Undefined offset:1. Here is my function.
public function post_order(){
$data = Input::all();
$count = count($data['invoice_no']);
$order = array();
for($i=0; $i<$count; $i++){
if(!empty($data['invoice_no'][$i])){
array_push($order, array(
'order_no' => $data['order_no'][$i],
'invoice_prefix' => $data['invoice_prefix'][$i],
'invoice_no' => $data['invoice_no'][$i],
'merchant_id' => $data['merchant_id'][$i],
'customer_id' => $data['customer_id'][$i],
'buytokri_order' => $data['order_name'][$i],
'name' => $data['name'][$i],
'pincode' => $data['pincode'][$i],
'address' => $data['address'][$i],
'landmark' => $data['landmark'][$i],
'city' => $data['city'][$i],
'state' => $data['state'][$i],
'country' => $data['country'][$i],
'mobile' => $data['mobile'][$i],
'subtotal' => $data['selling_price'][$i],
'payment_type' => $data['payment_type'][$i],
'txn_id' => $data['txn'][$i],
'shipping' => $data['shipping'][$i],
'total' => $data['subtotal'][$i]
));
}
}
Order::insert($order);
$var = $data['order_no'];
foreach ($var as $vars) {
$id = DB::table('ads_order')->where('order_no', $vars)->get();
}
$count = count($data['invoice_no']);
$orderhistory = array();
for($i=0; $i<=$count; $i++){
if(!empty($data['invoice_no'][$i])){
array_push($orderhistory, array(
'order_id' => $id[$i]->id,
'merchant_id' => $data['merchant_id'][$i],
'customer_id' => $data['customer_id'][$i],
'order_status' => $data['order_status'][$i],
'comment' => $data['comment'][$i],
'notify' => $data['notify'][$i],
'default' => $data['default'][$i],
'status' => $data['status'][$i]
));
}
}
Orderhistory::insert($orderhistory);
return Redirect::intended('/ordersuccess');
}