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run code in 300+ PHP versions simultaneously
<?php $arr = array ( 0 => 'nested array', 1 => 'nested array', 2 => 'nested array', 3 => 'nested array', 4 => 'nested array', 5 => 'nested array', ); $arr[null] = 'jam'; var_dump(key(array_diff(array_keys(array_values($arr)), array_keys($arr))))?:NULL;
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.7, 7.2.29 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
int(6)
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Parse error: syntax error, unexpected ':' in /in/qAJYd on line 13
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected ':' in /in/qAJYd on line 13
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/qAJYd on line 13
Process exited with code 255.
preferences:
244.56 ms | 401 KiB | 310 Q