阅读下面PHP代码,并选择输出结果( ) <?php class A{ public static $num=0; public function __construct(){ self::$num++; } } new A(); new A(); new A(); echo A::$num; ?> 0 1 2 3
<?php class A{ public static $num=0; public function __construct(){ self::$num++; } } new A(); new A(); new A(); echo A::$num; ?>
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