Stack is a linear data structure which follows a particular order in which the operations are performed. The order is LIFO(Last In First Out). We can implement it in both procedural or object oriented approach. Here i follow the procedural approach.
$data_array = [];
$top = -1;
function push($top, $item, $data_array){
global $top,$data_array;
$top++;
$data_array[$top] = $item;
return $data_array;
}
function pop(){
global $top,$data_array;
if($top < 0)
return -1;
$top_item = $data_array[$top];
unset($data_array[$top]);
$top--;
return $top_item;
}
push($top, 1, $data_array);
push($top, 2, $data_array);
push($top, 3, $data_array)
pop();