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<?php for ($i = 0; $i < 3; $i++) { static $age = 18; $age++; } var_dump($age);
based on 5pB0O
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 - 7.3.26, 7.4.0 - 7.4.16, 8.0.0 - 8.0.3
int(21)