Online PHP editor | output for 2duWj

Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6: Warning: Undefined array key "a" in /in/2duWj on line 9 Fatal error: Uncaught TypeError: array_values(): Argument #1 ($array) must be of type array, null given in /in/2duWj:9 Stack trace: #0 /in/2duWj(9): array_values(NULL) #1 {main} thrown in /in/2duWj on line 9
Process exited with code 255.
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.38, 7.0.0 - 7.0.31, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.25, 7.4.27 - 7.4.33: Notice: Undefined index: a in /in/2duWj on line 9 Warning: array_values() expects parameter 1 to be array, null given in /in/2duWj on line 9
Output for 7.3.32 - 7.3.33, 7.4.26: Warning: array_values() expects parameter 1 to be array, null given in /in/2duWj on line 9
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17: Notice: Undefined index: a in /in/2duWj on line 9 Warning: array_values(): The argument should be an array in /in/2duWj on line 9
Output for 4.3.0 - 4.3.1: Notice: Undefined index: a in /in/2duWj on line 9 Warning: array_values() [http://www.php.net/function.array-values]: The argument should be an array in /in/2duWj on line 9