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run code in 300+ PHP versions simultaneously
<?php $str = "моя строка"; $encoding = "UTF-8"; $first_letter = mb_strtoupper(mb_substr($str, 0, 1, $encoding), $encoding); $str = $first_letter . mb_substr($str, 1, mb_strlen($str, $encoding), $encoding); echo $str;

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41.88 ms | 402 KiB | 5 Q