Java Operators – Precedence of the + (Plus) Operator in Java

The inside of the println statement is this operation (d++) + (++d)

1. It is as follows, the value of d is read (d = 1)
2. current value of d (1) is put into the addition function

3. value of d is incremented (d = 2).

4. Then, on the right side, the value of d is read (2)

5. The value of d is incremented (now d = 3)

6. Finally, the value of d (3) is put into the addition function

   thus 1 + 3 results in the 4

edit: sorry for the format, I'm rather bad at using the list haha

Java evaluates expressions left to right & according to their precedence.

int x = 3, y = 7, z = 4;

x (3) += x++ (3) * x++ (4) * x++ (5);  // gives x = 63
System.out.println(x);

y = y (7) * y++ (7);
System.out.println(y); // gives y = 49

z = z++ (4) + z (5);
System.out.println(z);  // gives z = 9

Postfix increment operator only increments the variable after the variable is used/returned. All seems correct.

This is pseudocode for the postfix increment operator:

int x = 5;
int temp = x;
x += 1;
return temp;

From JLS 15.14.2 (reference):

The value of the postfix increment expression is the value of the variable before the new value is stored.