PHP基础(程序执行)

1.输出执行结果

<?php 

    $data = ['a' , 'b' , 'c' , 'd'];
    foreach( $data as $key => $value)
    {
        $value = &$data[$key];
         var_dump($data);
    }
?>

2.

<?php 

    $a = 0;
    $b = 0;
    if($a = 3 > 0 || $b = 3 > 0){
        $a++;
        $b++;
        echo $a;
        echo $b;
    }
?>

3.

<?php

    $count = 5;
    function static()
    {
        static $count;
        return $count++;
    }
    echo $count;
    echo ++$count;
    echo static();
    echo static();
?>

4.

<?php

    $var1 = 5;
    $var2 = 10;
    function foo(&$my_var)
    {
        global var1;
        $var1 += 2;
        $var2 = 4;
        $my_var += 3;
        return var2;
    }    
    $my_var = 5;
    echo foo($my_var)."\n";
    echo $my_var."\n";
    echo var1;
    echo var2;
    $bar = 'foo';
    $my_bar = 10;
    echo $bar($my_var)."\n";
?>