jQuery Forum

Hello, I recently learnt jQuery but I am having problems on working
with JSON. I am loading the JSON data from PHP file using $.getJSON.
The JSON returned is {"4":{"6":"1"},"3":{"1":"1","2":"1"}} and array
for reference is
Array
(
[4] => Array
(
[6] => 1
)
[3] => Array
(
[1] => 1
[2] => 1
)
)
The problem is that I don't know the JSON values. Is there any way I
can loop through JSON so I can access "4", its child "6" and value 1?
Or I will have to make another JSON structure?