Simple program question: The income order of the four projects of abcd accounts for 10%, 20%, 30%, and 40% respectively.

The income of the four projects of abcd accounts for 10%, 20%, 30%, and 40% respectively. When a project does not exist, the income of the project will be attributed to the previous project. Project a always exists, and a function is encapsulated to obtain the income of abcd;

This question is not difficult. The key point is to think of using arrays. If you think of this, you can definitely do it.

Program code:

/**
         * Get project income
       * @param null $b
      * @param null $c
        * @param null $d
                                                     */
function getIncome($b = null, $c = null, $d = null)
{
$income = ['a' => 0.1, 'b ' => 0.2, 'c' => 0.3, 'd' => 0.4];
                                                                                                         $income['d'] = 0;
      }
                                                                                                                                                         $income['              }! If (! $ B) {
$ income ['a'] += $ income ['b'];
$ Income ['b'] = 0;
} Return $ Income;

';
 var_dump(getIncome(1, 0, 0));
?>