3v4l.org

run code in 300+ PHP versions simultaneously
<?php $big = -1 * PHP_INT_MAX; echo bin2hex(pack('P', $big)); echo "\n"; $packed = pack('VV', $big & 0x00000000ffffffff, ($big & 0xffffffff00000000) >> 32); $bin = bin2hex($packed); echo $bin."\n"; $d = unpack('V2', $packed); echo str_pad(base_convert($d[2], 10, 16), 8, '0', STR_PAD_LEFT).str_pad(base_convert($d[1], 10, 16), 8, '0', STR_PAD_LEFT);

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46.89 ms | 402 KiB | 5 Q