int m=(l+h) >> 1; what does it mean?

Devakinandan
2 min readSep 8, 2024

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The expression int m = (l + h) >> 1; is used to calculate the midpoint of two integers l and h, typically in the context of a binary search algorithm or similar logic.

Breakdown:

  • l and h are two integer values.
  • l + h calculates the sum of l and h.
  • >> 1 is the bitwise right shift operator, which shifts the bits of the result to the right by one position. This effectively divides the sum by 2.

Meaning:

The expression (l + h) >> 1 is equivalent to performing integer division by 2 on the sum of l and h. Therefore, it computes the midpoint between l and h.

Example:

If l = 2 and h = 10, then:

  • l + h = 2 + 10 = 12
  • 12 >> 1 shifts the bits of 12 to the right by one position, resulting in 6.

So, m would be 6, which is the midpoint between 2 and 10.

Why use >> 1 instead of / 2?

In some systems, bitwise operations like >> 1 are slightly faster than division by 2, though in modern compilers, the difference is often negligible. It’s mostly a historical practice from earlier computing where optimization was crucial.

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Devakinandan
Devakinandan

Written by Devakinandan

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