I want to know why the output is (1), and why In the second assignment to variable b, the expression (i+=2) does not get evaluated. finally how does this program execute step by step? I am still a beginner.
`
int i = 0;
bool t = true;
bool f = false,
b;
b = (t && ((i++) == 0));
b = (f && (i += 2 > 0));
cout << i << endl;
`
Because the && operator short-circuits and f is false, 1 += 2 is not being evaluated.
Since the entire expression can only be true if both operands to && are true, there is no need to evaluate (i += 2 > 0) to determine that the value of the entire expression is false. Given the lack of need to evaluate the second operand in this scenario, many programming languages guarantee that it will not be, including C and C++.
Be careful about using operands with side-effects in boolean expressions.