I have made uva.onlinejudge.org my homepage in Firefox and when I went there yesterday, I saw this link. I checked the link and it had 4 problems: Different (very easy), Reverse Binary (easy), Coastal length (medium) and CatVsDog (Hard).
I was able to solve Different and Reverse binary in one attempt. Then, I started to code for Coastal length and found some interesting cases to solve. Need to find the right algorithm for this problem.