Demonstrate pre/ post increment operators better

[Locust1]

The second code snippet from the Unary section does not illustrate the core difference between the pre and post increment operators well (++i vs i++):
https://dev.java/learn/language-basics/using-operators/#unary

Both
System.out.println(++i);
and
System.out.println(i++);
produce the same output so it might be confusing as to what is the actual difference.

I would suggest replacing it with something along the lines of

int i = 3;

i++;
// prints "i = 4"
System.out.println("i = " + i);

++i;
// prints "i = 5"
System.out.println("i = " + i);

int j = ++i;
// prints "i = 6"
System.out.println("i = " + i);
// prints "j = 6"
System.out.println("j = " + j);

int k = i++;
// prints "i = 7"
System.out.println("i = " + i);
// prints "k = 6"
System.out.println("k = " + k);

[danthe1st]

Alternatively (instead of introducing two new variables), it might be a good idea to change the comments to include how the operators change the variables.
Something along the lines of the following (I'm just showing the idea, there's probably a better text for these things):

class PrePostDemo {
    public static void main(String[] args){
        int i = 3;
        i++;
        // prints 4
        System.out.println(i);
        ++i;               
        // prints 5
        System.out.println(i);
        // sets i to 6 and prints 6
        System.out.println(++i);
        // sets i to 7 and prints 6
        System.out.println(i++);
        // prints 7
        System.out.println(i);
    }
}