This problem involves two issues. One is the process of continuous calculation, and the other is what the result is.

Let's start with the first question. When calculating A= 16384*2, first calculate 16384*2, save the calculation result in a temporary variable, and then assign the value of this temporary variable to A. ..

Let me talk about the second question. What is the result of 16384*2? It is an integer because 16384 and 2 are both integers, so the calculation result is still an integer. And = 16384 * 2 = 32768, which is out of the integer range (-32768 to 32767) and overflows, and it will be reported as "overflow" at runtime.

To be clear, it is not the variable A that overflows, but the temporary variable.

How to use option a? Because 32768 is out of the integer range, it is treated as a long integer, and the result is still in the long range, so it is normal.

Because of 1.5, item B is treated as a haplotype and normal.

As for d, 190 and 2 are integers, and 190 2 = 36 100 seems to be overflowing. In fact, when calculating the power, the numbers before and after it are processed with double precision, so it will not overflow.