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

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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)

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