How do I align date formats

Hi, I have some dates I need converted to the same format. I've boiled it down to the following possible formats but now I'm stuck:

01/01/2016

1/01/2016

01/1/2016

1/1/2016

I need them all to be: 01/01/2016

I've tried a few things but nothing works without messing up something else at this point.

Answer 1

[Walter Roberson]

dates = {'01/01/2016', '1/01/2016', '01/1/2016', '1/1/2016'};
datestr(datenum(dates), 'dd/mm/yyyy')

Answer 2

[Peter Perkins]

Using datetimes, Walter's suggestion would look like

>> dates = {'01/01/2016'; '1/01/2016'; '01/1/2016'; '1/1/2016'};
>> datetime(dates,'Format','dd/MM/yyyy')
ans = 
   01/01/2016
   01/01/2016
   01/01/2016
   01/01/2016