C - How to get the 4 least significant bits in a Char

Question

I´m new in the C language, and I´m trying to get the 4 least significant bits from an unsigned char. So far I have no idea how to get them. I´ll appreciate any help

Well, `c & 0xF`. But what does this have to do with *arrays* — Antti Haapala -- Слава Україні, Mar 23 '19 at 18:53
https://stackoverflow.com/questions/295279/what-is-the-fastest-way-to-get-the-4-least-significant-bits-in-a-byte-c — Antti Haapala -- Слава Україні, Mar 23 '19 at 18:56

score 5 · Accepted Answer · answered Mar 23 '19 at 18:58

It's simple bitwise logic:

unsigned char c = 120;
unsigned char lsb4 = c & 0x0F;

Where 0x0F represents the binary value 00001111.

If you're using GCC, it's even more literal:

unsigned char lsb4 = c & 0b00001111;

Technically the leading 0s are not required here but they're included to help illustrate which bits are being selected.

C - How to get the 4 least significant bits in a Char

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