Actually i am not getting the use of increment or decrement ???

Answer 1

In what language?

a++
++a
a--
--a

Answer 2

As I wrote but with ; at the end. In this way, if you do that only for 'a' variable you can write

++a;

or

--a;

Answer 3

https://code.sololearn.com/WFRlItj060zt/?ref=app

Answer 4

increment will increase the variable value by 1 and decrement-- will decrease it by 1

Answer 5

In JavaScript..

Answer 6

--a decrements a before use
a-- uses a before decrement