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