Is there an easy way to remember the difference between x++ and ++x?

Question

I just started learning java and always confuse ++x with x++. It is very difficult to remember which one did what and how they can be used.

Answer 1

Look at the position of ++ in relation to x. In ++x the plus signs are before the x, so you plus 1 before you pass the value. In x++ the plus signs are after the x, so you plus 1 after you pass the value.

Answer 2

x = 2
y = ++x
z = x++

y = 3.
z = 2.

Answer 3

Yeah, if the value is first (x++) then assign the value before incrementing; if the increment is first (++x) then increment before assigning the value.

Answer 4

Soz, I really meant to say you need to test them seprately. Test this first in code playground:

int x = 2;
int y = x++;
Console.WriteLine(y);

This will output 2. Now test this second:

int x = 2;
int y = ++x;
Console.WriteLine(y);

This will output 3.

Answer 5

I fear I may have confused the issue with my rather poor first example. Honestly, it's really not that difficult once you get your head around it.

Just remember that ++x means increment first then assign value; and x++ means assign value first then increment.

Answer 6

@bagshot

They both equal 3.

Answer 7

Once you understand it, it shouldn't be difficult to memorize by the name:

x++ is called "postfix"
"post" means AFTER.

++x is called "prefix"
"pre" means BEFORE.

You can think of it as being before/after doing the operation.

Answer 8

do you have an example please bagshot? i lost a game becuase of this lol