18 lines
433 B
PHP
18 lines
433 B
PHP
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<?php
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function unique_chars(string $input, bool $multibyte = true): int {
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$chars = [];
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$strlen = $multibyte ? 'mb_strlen' : 'strlen';
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$substr = $multibyte ? 'mb_substr' : 'substr';
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$length = $strlen($input);
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for($i = 0; $i < $length; $i++) {
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$current = $substr($input, $i, 1);
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if(!in_array($current, $chars, true)) {
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$chars[] = $current;
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}
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}
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return count($chars);
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}
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