Evaluation of logical operand

Question

If I have the following:

int a = -10 && 0;

then does C evaluate -10 as 1 because -10 is different from 0 and then make the comparation between 1 && 0 to get 0 as result? Or does let -10 and make the comparation as written?

Instead if I write:

int c = 10;
int b = 11;

int res = c > 10 && b == 11;

then the C make this:

c > 10 is false so it evaluates to 0 while b == 11 is true so it evaluates to 1

then the expression is:

0 && 1 with 0 as result.

Answer 1

The operator && and || has short circuit behavior ¹ . In

int a = -10 && 0;  

since left operand is -10 , which is non-zero and hence true , therefore right operand, ie 0 is checked. In

int res = c > 10 && b == 11;  

since left operand is evaluated to false , right operand is not evaluated.

---

^{1 C11 6.5.13 (p4): If the first operand compares equal to 0 , the second operand is not evaluated.}

Answer 2

For

int a = -10&&0;

-10 is treated as higher logic(1). However, result still be 0.