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<?php function isQuadtree($bits, &$i = 0){ if ($i >= strlen($bits)) return false; if ($bits[$i] === "1") { isQuadtree($bits, ($i++)); isQuadtree($bits, $i++); isQuadtree($bits, $i++); return isQuadtree($bits, $i++); } return true; } var_dump(isQuadtree("110000"));
Output for 8.3.0 - 8.3.29, 8.4.1 - 8.4.16, 8.5.0 - 8.5.1
Fatal error: Uncaught Error: isQuadtree(): Argument #2 ($i) could not be passed by reference in /in/AlJYl:6 Stack trace: #0 /in/AlJYl(14): isQuadtree('110000') #1 {main} thrown in /in/AlJYl on line 6
Process exited with code 255.
Output for 8.1.34, 8.2.27 - 8.2.30
Fatal error: Uncaught Error: isQuadtree(): Argument #2 ($i) cannot be passed by reference in /in/AlJYl:6 Stack trace: #0 /in/AlJYl(14): isQuadtree('110000') #1 {main} thrown in /in/AlJYl on line 6
Process exited with code 255.

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