Why does a=(b++) have the same behavior as a=b++?

Question

I am writing a small test app in C with GCC 4.8.4 pre-installed on my Ubuntu 14.04. And I got confused for the fact that the expression a=(b++); behaves in the

Answer 1

Placing ++ at the end of a statement (known as post-increment), means that the increment is to be done after the statement.

Even enclosing the variable in parenthesis doesn't change the fact that it will be incremented after the statement is done.

From learn.geekinterview.com:

In the postfix form, the increment or decrement takes place after the value is used in expression evaluation.

In prefix increment or decrement operation the increment or decrement takes place before the value is used in expression evaluation.

That's why a = (b++) and a = b++ are the same in terms of behavior.

In your case, if you want to increment b first, you should use pre-increment, ++b instead of b++ or (b++).

Change

a1 = (b1++);

to

a1 = ++b1; // b will be incremented before it is assigned to a.