what is the output of this code

Question

int b=2;
int i=5;
i + =++ i*b;
cout<<i;

Answer 1

i += ++i*b
is equivalent to
i = i + ++i * b
unary operators have higher precedence so ++i is evaluated first so i becomes 6
*has higher precedence next, so 6*2 is 12

then i + 12 since I has already been incremented to 6, 6+12=18 will be the result.

Answer 2

actually 18

Answer 3

18