如何修复错误代码C4146“unary减运算符应用于unsigned type.result仍未签名”？

Question

Data type int 's minimum value is -2,147,483,648.

So, I typed

int val = -2147483648;

But, it has an error:

unary minus operator applied to unsigned type.result still unsigned

How can I fix it?

Answer 1

2147483648 is out of int range on your platform.

Either use a type with more precision to represent the constant

int val = -2147483648L;
// or
int val = -2147483648LL;

(depending on which type has more precision than int on your platform).

Or resort to the good old - 1 trick

int val = -2147483647 - 1;

Answer 2

-2,147,483,648 is interpreted as negation of 2147483648 . 2147483648 exceed maximum positive integer on your system and is considered as unsigned.

Instead, try

-2147483647 - 1