Simple Java For Loop Logic, Increments and Decrements [closed]

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I have here a simple Java Program. I am writing this to walk through the logic of the program step by step and verify why it returns the output that it does. I would appreciate any feedback on the way I'm interpreting this.

I'll display the program first, and then explain how it works afterwards.

public class Test9 {
    public static void main (String [] args) {
        int x = 0;
        int y = 10;
        for (int z = 0; z < 5; z++) {
            if ((y-- > 7) || (++x > 2)) {
                y--;
            }
        }
        System.out.println(y + "" + x);
    }
}

What is the output and why?

In order to know the correct output of this program, it's necessary to keep a running tally of all three int variables, x, y, and z, during the course of the "for" loop.

At the beginning of the loop, z=0, x=0, and y=10. It then proceeds to the if statement, where it looks to see if the current value of y is greater than 7. It's important to note that y-- means that it will post-decrement y by 1. Which means AFTER the conditional statement has been been decided True or False.

So, since y=10, currently, 10>7, and the statement is True. Since this conditional statement is true and it sees that an OR operator is next, it skips the ++x>2 since it doesn't need to know whether it is TRUE or FALSE. The contents of the loop are now performed, y--, which makes y=8. Decremented once in the conditional statement and once inside the if statement. x remains 0.

The next iteration begins with, z=1, y=8. x=0. The same rules apply, so 8>7, y will be decremented by 2 and x will remain the same.

The third iteration begins with z=2, y=6, x=0. This time around, 6>7 is false, but y is still post decremented. So y=5, and ++x>2, will evaluate as 1>2, since ++x is the prefix version and adds 1 before the operation takes place. Both operations are false, and y will not be decremented a second time.

The forth iteration begins with z=3, y=5, x=1. 5>7 is false, y is decremented to 4. 2>2 is false as well, therefore no 2nd decrement to y.

The fifth iteration begins with z=4, y=4, x=2. 4>7 is false, y is decremented to 3. 3>2 is true! So y will be decremented a 2nd time, to 2.

The ending values are y=2, x=3. Therefore the program output will be: 2 3

It's important to understand when the increments and decrements happen and when开发者_高级运维 they don't, especially when they are inside the conditional statements of an if statement, since it will impact the final output.

If there are terms/jargon, ways of saying things, or flaws in my logic please let me know. I'm trying to understand all the fundamentals of java. Thanks.

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You logic is correct... But what is actually the question?