I know there are several question about the x++ operation, I know the difference between ++x and x++. But now I have to solve this:
int x = 5; x += x++ * x++ * x++; Well I know that this shouldn't be too difficult, but still, I need an explanation how this calculatino is done, step by step, I don't get it by myself..
Your code is equivalent to:
int x = 5; int originalX = x; int a = x++; int b = x++; int c = x++; x = originalX + a * b * c; System.out.println("x = " + x); //215 
x += x++ * x++ * x++; can be written as:
x = x+ x++ * x++ * x++; how will it be evaluated? x= 5+(5 * 6 * 7) because you are using postfix. So, the incremented value of x will be visible from the second time it is used.
So, final output = 5+ (5*6*7) == 215 x++ would mean read the value and use it in the place which is referenced and then increment it.
So in your question:-
int x = 5; x = 5 + 5 * 6 * 7 x += x++ * x++ * x++; x = 215 
int x = 5; x += x++ * x++ * x++; First, set some brackets to better see the calculation sequence:
x += ((x++ * x++) * x++); Then, replace the first occurance of x with it's value, calculate, and continiue replacing with updated values:
5 += ((x++ * x++) * x++); 5 += ((5 * x++) * x++); 5 += ((5 * 6) * x++); 5 += ((5 * 6) * 7); 5 += 210; and now, it's plain math...
Result should be: 215
And my compile gives me: 215
So I think my explanation is correct. But i'm not 100% sure...
0 += x++ * x++ * x++,x += x++ * x++,x += (x++ * x++) * x++, etc.), or consult the JLS.