Can anyone explain exactly what the post- and pre- increment is, because from what I know, I'm just getting more confused?

shouldn't this be, 11 is good and 21 is bad? because, in case of i++, the value 10 first gets evaluated if equal to i, and then incremented?

int i = 10;
if(i++ == i){
 System.out.println(i + " is good");
}
else{
 System.out.println(i + " is bad");
}

int j = 20;
if(++j == j){
 System.out.println(j + " is good");
}
else{
 System.out.println(j + " is bad");
}

Output: 11 is bad 21 is good