Split array into unique pairs

Question

Say i start with a simple array (which could be theoretically of any length):

$ids  = array(1,2,3,4);

What it the best solution for splitti

Answer 1

Probably not the best solution

$ids  = array(1,2,3,4);

$pairs = array();
foreach($ids as $key => $data){
    foreach($ids as $subkey => $subdata){
        if( $subkey != $key){
            if(!in_array(array($subdata, $data) , $pairs) ){
                $pairs[] = array($data, $subdata);
            }
        }
    }
}

Anyway it works