Question : How to use OR condition in regular expression

Hi,
How to use OR condition in regular expression

my req is
YYYY/MM/DD format if the user enter  YYYY/M/DD also i want to accept ?
eg:
YYYY/MM/DD---- 2010/08/19
YYYY/M/DD  ---- 2010/8/19
in regular expression i worte YYYY/MM/DD
YYYY/MM/DD ---- /^\d{4}\/\(d){2}\/\d{2}$/
but i dont know how to but or condition ??

How can i do that ??

Answer : How to use OR condition in regular expression

/^\d{4}\/\d{1,2}\/\d{2}$/