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<?php $string = '' $regx = '(\\d)(?=(\\d{3})+$)'; $string = '919191911'; $pattern = '(\\d)(?=(\\d{3})+$)'; $replacement = '$1$4 $2$3$5'; echo preg_replace($pattern, $replacement, $string);
Output for 5.4.0 - 5.4.27
Parse error: syntax error, unexpected '$regx' (T_VARIABLE) in /in/83LiK on line 5
Process exited with code 255.
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.28
Parse error: syntax error, unexpected T_VARIABLE in /in/83LiK on line 5
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 T_VARIABLE in /in/83LiK on line 5
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/83LiK on line 5
Process exited with code 255.

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