问题
When programming in C, say if I have integer h as a hexadecimal value and integer d as a decimal number. Can I do addition or subtraction between h and d? Or do they have have to be in the same number system?
回答1:
Yes, you can write:
int x = 100 - 0x100 + 0100;
That mixes decimal with hex and octal. The values are all converted to binary anyway before the calculation occurs (and the compiler will do the calculation in this example; it won't be evaluated at runtime). And any of the constants can be replaced by an int value that was assigned the appropriate value:
int d = 100;
int h = 0x100;
int o = 0100;
int x = d + h + o;
回答2:
Yes they can, for example
int x;
x = 0x0F + 10;
printf("%d\n", x);
Output:
25
the representation you use doesn't matter, it will be ultimately all converted to binary after all.
来源：https://stackoverflow.com/questions/28445459/can-hexadecimal-numbers-be-added-subtracted-with-decimal-numbers