I have made two solutions.. 1st one was failing at test case#5 and second one was failing @test case#2.
Then I combined both and took the minimum out of both and in this case its again failing @test case#2.

If you analyse, 1st one was failing@ Test Case#5 so its answer was proper for Test case#2.
Now I took the minimum of 1st and 2nd solution and its again failing @Test case#2. That means my 2nd solution is giving minimal output than 1st one.

So I can say that the Test case#2 is wrong.

may be your 2nd solution is wrong although it luckily passes test1?

>  So I can say that the Test case#2 is wrong.

99.99% of all posts saying "test X is wrong" are wrong :).

Of course, if your WA2 code calculates a smaller value for test #2 than your WA5 code (which gets the correct answer for #2),  then your combination algorithm will yield the wrong result for test #2.