5/14-5/20 CareerCup 5.6

Write a program to swap odd and even bits in an integer with as few instructions as possible (e.g., bit 0 and bit 1 are swapped, bit 2 and bit 3 are swapped, etc).

https://github.com/writecoffee/c ... blob/master/5.6.cpp


/////////////////////////////////////////////////////////////////////////////////
// create two masks: odd_mask records all the bits in odd positions and even_mask
// records all the bits in even positions; right shift the even_mask and left
// shift the odd_mask. excluding the odd(even) mask generating procedure, 5
// operations are taken
/////////////////////////////////////////////////////////////////////////////////

方法跟书上的一样

同上。想不出什么别的好方法

书上的似乎还是有bug。负数的arithmetic right shift带符号一起移动，java里应该改为>>>才是logical right shift把。负数会错
https://github.com/zyli5313/CareerCup/blob/master/5-6.cpp