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<?php function format_date($d) { $m = array(); preg_match('/(\d{4})[\.-\/](\d{2})[\.-\/](\d{2})/', $d, $m); if (count($m) == 4) { $d = "$m[2]/$m[3]/$m[1]"; } return $d; } print_r(format_date('2015-01-01')).PHP_EOL; print_r(format_date('2015/01/02')).PHP_EOL; print_r(format_date('2015.01-03')).PHP_EOL;

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