3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = 65; $x = ~$a + 1; // -65 in 2s complement printf("%3d = 0x%x\n\n",$a,$a); printf("%d = 0x%x\n",$x,$x);

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49.68 ms | 402 KiB | 5 Q