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POWhere can I find a bit shifting guide for C?
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copied!<p>I have looked at <a href="https://stackoverflow.com/questions/141525/absolute-beginners-guide-to-bit-shifting">What are bitwise shift (bit-shift) operators and how do they work?</a> but I still find the concept of bit shifting difficult to understand.</p> <p>Can someone point me in the direction of a more basic guide to bit shifting in C. I expect it will be something really long since it will need to cover the whole subject.</p> <p>I really do not understand it but I want to learn it, so any help would be appreciated.</p> <p>I am learning the k&r, and that is what this is for so I can do the exercises. I understand the basics, but I still cannot do correct bit shift operations.</p> <p><strong>EDIT here's the exersices from K&R that have stumped me</strong></p> <p>Exercise 2-6: Write a function setbits(x, p, n, y) that returns x with the n bits thatbegin at position p set to the rightmost n bits of y, leaving the other bits unchanged.</p> <p>Exercise 2-7: Write a function invert(x, p, n) that returns x with the n bits that begin at poisiton p inverted (i.e., 1 changed into 0 and vice versa) leaving the others unchanged.</p> <p>Exercise 2-8: Write a function rightrot(x, n) that returns the value of the integer x rotated to the right by n bit positions</p> <p>Exercise 2-9: In a two's complement number system, x &= (x-1) deletes the rightmost 1-bit in x. Explain why, Use this observation to write a faster version of bitcount</p> <p>These are exercises from the k&R (the c programming language) book its the best c book there is but I am having trouble understanding bitshifting so I am having problems with these exercises.</p>

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