Why does
((255<<24)|(255<<16)|(255<<8)|255)>>>0
equals 4294967295 when
Math.pow(256,4)
equals 4294967296?
Notice that the bitwise operation is one short. Why is this?!
Why does
((255<<24)|(255<<16)|(255<<8)|255)>>>0
equals 4294967295 when
Math.pow(256,4)
equals 4294967296?
Notice that the bitwise operation is one short. Why is this?!
Share Improve this question edited Sep 16, 2012 at 2:18 Peter Mortensen 31.6k22 gold badges110 silver badges133 bronze badges asked Sep 12, 2011 at 20:24 talentedmrjonestalentedmrjones 8,1711 gold badge28 silver badges27 bronze badges2 Answers
Reset to default 12Because zero takes up a binary value.
4294967296 is the number of "slots" that 32 bits gives you, 4294967295 is the decimal number occupying highest slot.
Because the first one is 2^32-1, and the second one is 2^32? You know that with the first "statement" you are setting to 1 the first 32 bits of a value, right?
In 32 bits, the first bit is "valued" 1, the second 2, the third 4... The 32th 2147483648. Their sum is 4294967295 :-)
Let's make an example with 8 bits.
Math.pow(256,1) == 256
1 + 2 + 4 + 8 + 16 + 32 + 64 + 128 = 255.