I don't understand why

Question

The output of this piece of code is 9.
int a = 5;
int b = 4;
while (b-- != 0) ++a ;
System.out.print(a);

Can someone please explain why?

Answer 1

Yes, I can:

You chose to use:

While( somthing ) do one thing

Instead of

While( somthing ){ do everything between brackets }

So the loop will do b-- and ++a, giving this set of b/a
4/6
3/7
2/8
1/9
0 --> because you post decrease b it will first execute and then subtract 1 from b

Print( 9 )

Because this isn't in your loop (using the first example of while loop will only execute one thing) you will only get the output after the loop, and not while looping

Answer 2

Well I'm pretty sure the answer is right you basically asked for 3+6

b-- = 3
a++ = 6

Answer 3

thanks for the answer Roel