who has the most efficient way ?

[kimberlc]

I have an array.

If there are duplicate values in the array I want to load them into another array only ONCE .

I will use this other array to notify users that there was a duplicate(s)..

What is the most efficient way to do this ?

Thanks,
ck

[planetsim]

There are quite a few ways for it to be done however

if (in_array("myValue",$theArray)) {
    //use the temp Array
    if (!in_array("myValue",$tempArray)) {
       $tempArray[]="myValue";
    }
} else {
   $theArray[]="myValue";
}

That probably isnt what you want however it should give you an indication of what should probably happen.

[Bunkermaster]

// base array
$input = array("a" => "green", "red", "b" => "green", "blue", "red"); 
// clean array
$result = array_unique($input);
// get differences (duplicate keys)
$result = array_intersect($result, $input);
// clean up duplicate keys array
$result = array_unique($result);

this of course can be done in ONE pass, although you lose readability and therefor maintainability

// base array
$input = array("a" => "green", "red", "b" => "green", "blue", "red"); 
$result = array_unique(array_intersect(array_unique($input), $input));