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How to reverse Bits in a 32 bit word
- Thread starter rsnambiar
- Start date
paulfrance
Programmer
Do you mean reverse each bit ie. 1110 to 0001 which could be done like this using the NOT operator:-
int val;
val = ~val;
Or do you mean reverse the order of the bits ie. 1110 to 0111 which could be done like this(assumes that your implementation uses 32bit ints):-
int val, temp, i;
val = 0xFFF03001; /*for example*/
temp = 0;
for (i=0; i < 32; ++i)
{
temp <<= 1; /* left shift one place */
temp |= (val & 1);
val >>= 1; /* right shift one place */
}
val = temp; /* val should now be 0x800C0FFF */
Hope this helps, sorry about the lack of explanation,
paulf
int val;
val = ~val;
Or do you mean reverse the order of the bits ie. 1110 to 0111 which could be done like this(assumes that your implementation uses 32bit ints):-
int val, temp, i;
val = 0xFFF03001; /*for example*/
temp = 0;
for (i=0; i < 32; ++i)
{
temp <<= 1; /* left shift one place */
temp |= (val & 1);
val >>= 1; /* right shift one place */
}
val = temp; /* val should now be 0x800C0FFF */
Hope this helps, sorry about the lack of explanation,
paulf
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