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<?php $str = '20170131'; $a = str_split($str, 4); $b = str_split($a[1], 2); var_dump("{$b[1]}-{$b[0]}-{$a[0]}");
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
string(10) "31-01-2017"
preferences:
109.7 ms | 1943 KiB | 4 Q