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<?php $array = array(0 => 100, "color" => "red"); $keys = array_keys($array); print_r($keys[1]); echo $dd = count($key); ?>
Output for 8.0.10 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
color Warning: Undefined variable $key in /in/X3qsq on line 6 Fatal error: Uncaught TypeError: count(): Argument #1 ($value) must be of type Countable|array, null given in /in/X3qsq:6 Stack trace: #0 {main} thrown in /in/X3qsq on line 6
Process exited with code 255.
Output for 8.0.0 - 8.0.9
color Warning: Undefined variable $key in /in/X3qsq on line 6 Fatal error: Uncaught TypeError: count(): Argument #1 ($var) must be of type Countable|array, null given in /in/X3qsq:6 Stack trace: #0 {main} thrown in /in/X3qsq on line 6
Process exited with code 255.
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
color Notice: Undefined variable: key in /in/X3qsq on line 6 Warning: count(): Parameter must be an array or an object that implements Countable in /in/X3qsq on line 6 0
Output for 7.3.32 - 7.3.33
color Warning: count(): Parameter must be an array or an object that implements Countable in /in/X3qsq on line 6 0
Output for 5.0.4 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33
color Notice: Undefined variable: key in /in/X3qsq on line 6 0
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.3
color Notice: Undefined variable: key in /in/X3qsq on line 6 0

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