hello, 😕
I have 4 arrays... i need to intersect their elements (array_intersect).
The problem is that i need to check every array to see if is empty(no elements). If there is one(or two/or three/or all the four->message)empty, then the array must be cut off from array_intersect function...
thx !!!

    [man]empty/man or [man]count/man will tell you if an array is "empty" or doesn't have any elements.

    What have you tried so far?

      i don't know how 2 write the algorithm....with 16 if ????

        -if count() of all arrays are >0
        array_intersect(array1, array2,array3, array4)
        -if count(array1) is ==0 then
        array_intersect(array2,array3, array4)
        -if count(array2) and count(array4) ==0 then
        array_intersect(array1,array3)
        .....and so on ....

          Two things that would reduce that code down to something that looks more intelligent: [man]references[/man] and the [man]call_user_func_array/man function. For example, you could build an array of references to non-empty arrays like so:

          $arrays = array(&$array1, &$array2, &$array3, &$array4);
$arrays = array_filter($arrays);

          Now you simply call [man]call_user_func_array/man to invoke the 'array_intersection' filter on the non-empty arrays.

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