Someone explane what is --x?

Answer 1

b will equal -2

Answer 2

Decreases x by 1 and returns the new value.

Answer 3

It's means the original value the at has been initialized - 1 e.g x = 2, - - x = x - 1

Answer 4

thanks

Answer 5

Consider the following example code:
int x = 0;
int a = x--;
int b = --x;

"a" would equal 0 since the decrement occurs AFTER the assignment.
"b" would equal -1 since the decrement occurs BEFORE the assignment.