```
<form action='' method='post'>
    Trip date: <input type="date" name="trip_date[]" class="input-xlarge  datepicker" value="<?php echo date("m/d/Y");?>">
    Trip Date: <input type="date" name="trip_date[]" class="input-xlarge  datepicker" value="<?php echo date("m/d/Y");?>">
</form>

$form_data  = array(    
    'company_id'              => $_POST["company_id"],      
    'date'                    => $_POST["trip_date"]
);

```

I got the dates this format m/d/y by third party date picker function from my from when it's being submitted. 
My problem is when i try to convert the date format by writing like that: 

```
  date('Y/m/d',strtotime($_POST["trip_date"]));

```

i got the below

```
Warning: strtotime() expects parameter 1 to be string, array given in

```

How can i change array type date input format to my need date format?