<?php
$ranking[] = ['App', 'Views'];
$options[] = ['A', 'B'];
$flat = iterator_to_array(new RecursiveIteratorIterator
(new RecursiveArrayIterator
($options)), 0);
PD9waHAKCiRyYW5raW5nW10gPSBbJ0FwcCcsICdWaWV3cyddOwokb3B0aW9uc1tdID0gWydBJywgJ0InXTsKCiRmbGF0ID0gaXRlcmF0b3JfdG9fYXJyYXkobmV3IFJlY3Vyc2l2ZUl0ZXJhdG9ySXRlcmF0b3IobmV3IFJlY3Vyc2l2ZUFycmF5SXRlcmF0b3IoJG9wdGlvbnMpKSwgMCk7CnZhcl9kdW1wKGFycmF5X21lcmdlKCRmbGF0LCAkcmFua2luZ1swXSkpOw==