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<?php $color = str_split('0F000000', 2); $w = 1; $h = 1; $r = $color[0]; $g = $color[1]; $b = $color[2]; $a = $color[3]; $packed = pack("V2C4", $w, $h, $r, $g, $b, $a); print bin2hex($packed);

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25.96 ms | 402 KiB | 5 Q