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Let's do a speedy run-down on bitwise operators | |
First, know or recall that we can write the number 12 in three different ways | |
int twelve_dec = 12; | |
int twelve_hex = 0xC; | |
int twelve_bin = 0b1100; | |
bitwise operators operate bit-by-bit | |
NOT (complement) ~00000001100 = 11111110011 | |
OR 0b1100 | 0b1010 = 0b1110 | |
AND 0b1100 & 0b1010 = 0b1000 | |
XOR ^ 0b1100 ^ 0b1010 = 0b0110 | |
shift left << 0b0011 << 2 = 0b1100 | |
shift right >> 0b1100 >> 1 = 0b0110 | |
don't forget these mostly apply to booleans, with | |
false as 0 | |
true as 1 | |
in an if statement anything that isn't 0 is true is true | |
use ! instead of ~ | |
a ? b : c; | |
Applications: | |
cryptography | |
m = (m ^ k) ^ k | |
swap without a temp | |
val1, val2 | |
val1 = val1 ^ val2 | |
val2 = val1 ^ val2 | |
val1 = val2 ^ val1 | |
upper and lowercasing | |
chr & 0xdf | |
RGB | |
color & (0xff) | |
times and divide two | |
>> n | |
<< n |
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