848 B
848 B
Setting a bit
Use the bitwise OR operator (|) to set a bit.
number |= 1 << x;
That will set bit x.
Clearing a bit
Use the bitwise AND operator (&) to clear a bit.
number &= ~(1 << x);
That will clear bit x. You must invert the bit string with the bitwise NOT operator (~), then AND it.
Toggling a bit
The XOR operator (^) can be used to toggle a bit.
number ^= 1 << x;
That will toggle bit x.
Checking a bit
You didn't ask for this but I might as well add it.
To check a bit, shift the number x to the right, then bitwise AND it:
bit = (number >> x) & 1;
That will put the value of bit x into the variable bit.
Changing the nth bit to x
Setting the nth bit to either 1 or 0 can be achieved with the following:
number ^= (-x ^ number) & (1 << n);
Bit n will be set if x is 1, and cleared if x is 0.