How C# or any other language NOT Equal to operator performs

Hi which one is faster

            int a = 100;
        //First Way
        if (a != 100)
        {
            //Do something when a is not equal to 100
        }
        else
        {
            //Do something when a is equal to 100
        }

        //Second Way
        if (a == 100)
        {
            //Do something when a is equal to 100

        }
        else
        {
            //Do something when a is not equal to 100
        }

I thinks second way is faster , but I am curious to Know how NOT EQUAL (!=) operator is solved . Is it like first it implements equal(==) operation and then the result is negated like !(a==100) ? Any help will be highly appericiated.

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There is no difference between the two whatsoever. For an int , it all boils down to one of two assembly instructions on x86:

je - Jump if equal

jne - Jump it not equal

These, or any of the jxx instructions all take the same amount of time.

See also my other answer related to your question.

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Since you really seem to care, I suggest you test it yourself. Write up two loops, one that uses == and one that uses != . Then time them with a System.Diagnostics.Stopwatch , by wrapping them in calls to Start() and Stop() . Then compare. With a high enough number of iterations through the loop (to minimize other timing errors like context switches, interrupts, etc.) you will see no difference.

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I think on the binary level, it's a single operation (don't quote me), so either is pretty much the same.

That said, if you're trying to optimize at this level, you're doing something wrong. This isn't assembly.

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In my opinion, generally, the NOT EQUAL operation (!=) should be faster than EQUAL (==), as the NOT EQUAL operation will return result as soon as there's some chunk value (it based on your OS is 32-bit or 64-bit or so on) is not equal.

In your case, 2 operations should be faster equal, as 100 is an 4-byte integer.

And I think the 2 operator does not have the same implementation.

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