Java: Prefix/postfix of increment/decrement operators?

Question

From the program below or here, why does the last call to System.out.println(i) print the value 7?

class PrePostDemo {
     public          


        

Answer 1

Well think of it in terms of temporary variables.

i =3 ;
i ++ ; // is equivalent to:   temp = i++; and so , temp = 3 and then "i" will increment and become     i = 4;
System.out.println(i); // will print 4

Now,

i=3;
System.out.println(i++);

is equivalent to

temp = i++;  // temp will assume value of current "i", after which "i" will increment and become i= 4
System.out.println(temp); //we're printing temp and not "i"