Write a C++ program that prompts the user to input an integer (n) and outputs the sum of all integers i from 1 to n, but if i = 2^j (j is an integer) then i will have a negative sign.

For example, for n=8 the sum is equal to -1-2+3-4 + 5 +6+7 -8=6, because 1, 2, 4 and 8 are 2⁰, 2¹ , 2² and 2³ respectively while 3, 5, 6, and 7 are not equal to 2^j for any integer j.

Note: Solve this question without defining any other function apart from the main function.