(PHP 4 >= 4.0.5)
array_reduce -- Iteratively reduce the array to a single value using a callback functionArray_reduce() applies iteratively the callback function to the elements of the array input, so as to reduce the array to a single value. If the optional intial is avaliable, it will be used at the beginning of the process, or as a final result in case the array is empty.
This will result in $b containing 15, $c containing 1200 (= 1*2*3*4*5*10), and $d containing 1.
See also array_filter(), array_map().