Why can not one use "num++" instead of num = num +1

Answer 1

You can use both. Both will increment by 1.

Answer 2

Why do you think you can't use num++ ?

Answer 3

More than that, you can use:
1) num++
2) num = num + 1
3) num+=1
Here no difference between these expressions

Answer 4

Thank you all nice community