What is the purpose of bitwise shifting?

Question

I never really used bitwise shifting, and I'm kind of taking interest in it now. I get the basic idea; but is all bitwise shifting used for is an alternative to arithmetic? Or is there something deeper then CPU efficient math that I'm missing?

deonejuan · Accepted Answer

If you pack an integer by flipping the individual bits, you can then check the new value of the integer (which would be 31 bits long). That way, you can have code that checks a poker hand using a number like 12 decimal to know that particular hand was 2-of-a-kind (binary 0000011000 ). To determine the same thing otherwise would take a big if() else if() else() tree.

Bit flipping becomes exceptionally useful in 3D graphics, that would be your concept of the arithmetic.

What is the purpose of bitwise shifting?

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