Need help, please

Question

I did a challenge and I got this question:

int a=5;
switch(a) {
case 1 = ++a;
case 5 = ++a;
default = ++a;
}
System.out.print(++a);
System.out.print(--a);

the answer was: 87.

Can somebody please give me an explenation to this, why is that so, I just don't get it.

Answer 1

If we ignore the syntax errors,

case 5 will be executed: ++a will make a = 6

Since there is no break after case 5, default case will also be executed:
++a will make a = 7

When it prints ++a, pre-increment will assign 8 to both a and ++a
So, it'll print 8
When it prints --a, pre-decrement will assign 7 to both a and --a
So, it'll print 7

Both the values are printed without any space, so the output will be: 87

Answer 2

wow, never thought it could be that tricky. Thanks a lot, this really helped me understand how it works. :)

Answer 3

I bet this code will never run.
There are syntax errors.
How the hell was it approved by Sololearn ?

Answer 4

That's my bad, sorry.
Instead of "=" comes ":" in switch statement.