Difference between b=b++ and b++ [duplicate]

Answer 1

Because this is the order of execution of b = b++:

1. Get the value of b into some temp (probably into a bytecode register); this is the first part of b++, since it's a post-increment
2. Increment and store the incremented result in b (the second part of b++)
3. Assign the value from Step 1 to b (the result of the =)