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run code in 300+ PHP versions simultaneously
<?php function count_char($str) { $chars = str_split($str); $char_counter = array(); foreach($chars as $char) { if (ctype_alpha($char)) { if (!isset($char_counter[$char])) { $char_counter[$char] = 1; } else { ++$char_counter[$char]; } } } ksort($char_counter); return $char_counter; } var_dump(count_char("Hello World"));
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 - 8.1.30, 8.2.0 - 8.2.25, 8.3.0 - 8.3.13
array(7) { ["H"]=> int(1) ["W"]=> int(1) ["d"]=> int(1) ["e"]=> int(1) ["l"]=> int(3) ["o"]=> int(2) ["r"]=> int(1) }
preferences:
76.8 ms | 408 KiB | 5 Q