Invariant...

I kind of find it hard to find the loop invariant.
It's not very clear that what are the algorithms
to find the loop invariant.
Also, how to prove the correctness of loops
seems more difficult than the recursion....
Nested loop is even worse......
I hope I can figure it out by next week and
I hope I can do well on Test 2!~

Assignment2 done!

Fortunately, I have figured out most of assignment 2.
I found that "if you were frustrated yesterday, it doesn't mean
there is no hope everafter".
5 minuts ago, it was a bit trouble, and now it becomes all clear.

People need think. In this way, they can realize how much they
actually know. Or people will never know they can do such
things...

Though the road is full of challenges, we can go through it if
we believe we can..

Assignment 2....headache

I just started assignment 2 and I feel that it's alot harder than the first one.

The first question, I feel that we have met the hardest question about a tree.
I have a little bit insight about small part of the formula,
but I still feel headache about drawing trees.

The second was easy to unwind the expression. However the closed form is
not easy. I'm not sure whether we should let it smaller than certain number
or let it equal to an expression. Also, the constant ting annoys me.

I didn't start reviewing the next 2 quesion but I hope they will be easier.

after the first test

I have just wrote the first midterm test and
I found it easy since it's all about induction.

The first time I new the technique of proving using induction,
I thought it doesn't make sense, because we can have many flaws.
However now, I feel that for some specific proofs, induction is great!

For one of the question in the test,
I am wondering if we need a lemma....

anyway~ hope this one is the worst, and hope I can do better and better. ^ ^