After Test 2..

Since there is always a lot of people there in the day section, i wrote the night section test.
I don't know how big the difference between the day section and night section test. They may follow the same patter pretty much. I didn't work out satisfying answers on the test.
About the palindrome, i remembered well that i did the same thing in CSC108 lab. But one thing
to regret is that i forgot the prove structure. I tried using complete induction but i didn't organize the frame well.
Related to the last question in the test, i really got a mess in my mind during the test.
I got frustrated when i could not figure out right away the main purpose of the function downward(n). Things happened and i got all blank in my brain. When i got calm down and refreshed my mind, i tried out some typical examples. Unfortunatley, i didn't realize that the loop invairant was sth like the floor of lgn until hours after the test. Anyway i cannot say i fail the test, at least i failed getting an insight on the subtle things.