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bithacks
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| a.1 = a | |
| a.0 = 0 | |
| a+1 = 1 | |
| a+0 = a | |
| a^1 = ā | |
| a^0 = a | |
| ~-a = a-1 | |
| -a = ~a+1 // Two's complement | |
| unset rightmost set bit: a & (a-1) | |
| set rightmost unset bit: a | (a+1) | |
| get rightmost set bit: a & -a , also a^(a&(a-1)) | |
| clear trailing bits: a & (a+1) | |
| set trailing bits: a | (a-1) | |
| get ith bit: a & (1u << i) | |
| unset ith bit: a & ~(1u << i) | |
| set ith bit: a | (1u << i) | |
| a&(a+1) | |
| a&(a-1) | |
| useful masks: | |
| 0x1 = 0b00000000000000000000000000000001 = 1 | |
| 0xFFFFFFFF = 0b11111111111111111111111111111111 = -1 | |
| 0xAAAAAAAA = 0b10101010101010101010101010101010 = 2863311530 | |
| 0x55555555 = 0b01010101010101010101010101010101 = 1431655765 |
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