[! definition] A bitwise operation operates on a bit string, a bit array or a binary numeral at the level of its individual bits. Wikipedia
From Bard
Imagine you have a bunch of light switches - each switch representing a single bit, either on (1) or off (0). Bitwise operations are like playing with these switches to achieve different effects. Here are some common ones:
AND: Think of it like checking if both switches are on. If both are on, the output is 1, like a high five between switches.If either is off, the output is 0, like a silent treatment.
OR: This is like checking if at least one switch is on. If either or both are on, the output is 1, like a cheering crowd with at least one person clapping. If both are off, it’s silence again (0).
XOR: This is like a mischievous friend flipping switches. If a switch is on, it turns off and vice versa. So, if both are the same (both on or both off), the output is 0, like no change. If they’re different, the output is 1, like a surprised gasp for the unexpected change.
Shifting: Imagine moving all the switches to the left or right. Left shift doubles the value (like multiplying by 2), while right shift halves it (like dividing by 2). Think of it as pushing the switches left or right.
NOT: This is like a grumpy switch - whatever the input, it flips it. If it’s on, it becomes off, and vice versa. It’s like a stubborn child saying “no” to everything.
Here are some examples in Swift and Python:
[! Example] Swift:
let a = 5 // 0101 in binary
let b = 7 // 0111 in binary
let andResult = a & b // 0101 & 0111 = 0101 (only where both are on)
let orResult = a | b // 0101 | 0111 = 0111 (at least one is on)
let xorResult = a ^ b // 0101 ^ 0111 = 0010 (different bits are on)
let leftShiftResult = a << 1 // 0101 << 1 = 1010 (doubled)
let rightShiftResult = b >> 2 // 0111 >> 2 = 0001 (halved)
let notResult = ~a // ~0101 = 1010 (all bits flipped)[! Example] Python:
a = 5 # 0101 in binary
b = 7 # 0111 in binary
andResult = a & b # 0101 & 0111 = 0101 (only where both are on)
orResult = a | b # 0101 | 0111 = 0111 (at least one is on)
xorResult = a ^ b # 0101 ^ 0111 = 0010 (different bits are on)
leftShiftResult = a << 1 # 0101 << 1 = 1010 (doubled)
rightShiftResult = b >> 2 # 0111 >> 2 = 0001 (halved)
notResult = ~a # ~0101 = 1010 (all bits flipped)Remember, these are just basic examples. Bitwise operations can be combined and used in complex ways to achieve diverse functions, making them a powerful tool for programmers.
Hopefully, this helps you understand these fascinating operations in a simple way! Feel free to ask if you have any further questions.