[PHP-WIN] Array question

[Disko_kex]

If I have an array like this > [0] => 1 [1] => 2 [2] => 3 ... [99] =>
100
 
If I want to select [50] => 51 and store the value that's 2 positions
before and 1 position after, how can I do?
 
If I want to know what position value 71 have?
 
 
I have search the PHP-manual and found some functions as prev, next, pos
etc. But with these commands I have to loop thru the array every time to
reach the the values and positions. It has to be an easier way to do it.
 
// jocke