Best division questions in May 2012

Which is better option to use for dividing an integer number by 2?

151 votes

Which of the following techniques is the best option for dividing an integer by 2 and why?

Technique 1:

x = x >> 1;

Technique 2:

x = x / 2;

Here x is an integer.

Use the operation that best describes what you are trying to do.

  • If you are treating the number as a sequence of bits, use bitshift.
  • If you are treating it as a numerical value, use division.

Note that they are not exactly equivalent. They can give different results for negative integers. For example:

-5 / 2  = -2
-5 >> 1 = -3

(ideone)