The life is like this.
I don't know why this 1000 points problem is much easier than the 500 points one. And I don't know why the sample tests of the first two problems will be so weak. And I also don't know what the problem setters were thinking of when they came up with such problem set.
I've found that if I solve the third problem first instead of the first two, I could easily become a target. But now my rating have been changed from 2981 to 2794.
Now my face is looking like this: