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Fatal error: Uncaught TypeError: sizeof(): Argument #1 ($value) must be of type Countable|array, null given in /users/2021/i2151029/public_html/2022/WebProg/ch04/exam04-11.php:13 Stack trace: #0 {main} thrown in /users/2021/i2151029/public_html/2022/WebProg/ch04/exam04-11.php on line 13