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<?php declare(strict_types=1); function isPerfect($n) { return count($n)==4&&$n[0]*$n[1]*$n[2]*$n[3]+1==$n[0]**2+3*$n[0]+1**2); } var_dump(isPerfect(['a','b','c','d']));
Output for 5.6.8 - 5.6.14
Warning: Unsupported declare 'strict_types' in /in/Sb740 on line 2 Parse error: syntax error, unexpected ')' in /in/Sb740 on line 5
Process exited with code 255.
Output for 5.4.1 - 5.4.45, 5.5.24 - 5.5.30
Warning: Unsupported declare 'strict_types' in /in/Sb740 on line 2 Parse error: syntax error, unexpected '*' in /in/Sb740 on line 5
Process exited with code 255.

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