Yes! The problem statements were not very clear. Even if the problems lacked explanations of the test cases, the doubts in the comment sections were unanswered. These things are very sad. 
awful I/O format , this is what i can say!
I wonder how did u searched it 
Copying codechef’s question in codechef itself XD. Pro level :P.
Are you sure that the rest 3 are not copied ? XD
2 are Pattern Finding. And I don’t if the other problem is copied.
oh, and the 50k prize was a joke too, one of my friends at uem told me! (after i wasted my time in that contest)
actually that is a SPOJ question. (question was posted in SPOJ before codechef)
for pattern finding, there are sources too.
prize money is a joke! That too on such an international online platform like CodeChef is really something quite unexpected. @admin please have a look into such matters. 
@swetankmodi - Are you sure about the correctness of your claim? Because making a contest with no intention of giving prizes sounds like direct fraud to me if I put it bluntly.
yupp pattern should never be given directly as they did, it can be easily found on oeis
I googled the important parts of the problem statement.
You always have the option to report this to mod via mail, OR use the thread which I exclusively put up so that you guys can ask questions.
https://www.codechef.com/hostyourcontest/guidelines/
According to codechef’s guidelines, you can have copied questions in a closed contest.
I don’t see any point in having all copied questions in an online long contest. They didn’t even bother changing the stories. Many of them had the exact same Problem name too. A simple google search gives the original source.
@admin is taking action. Thank you 
@abdullah768 - Copied questions are allowed only in clsoed contests, i.e. local contests limited to your college etc. Usually where you can make contestants devoid of google.
Thanks for reporting this. We are looking into it.
Oh my bad, I thought anything which wasn’t there in the ongoing contest list was a closed one and were ignored by admin. Glad to be proven wrong 
Thanks a lot @admin for the quick action. My faith in humanity is restored.
Regards,
The Dark Knight.
@vijju123 I got the prize from UEMCO last week so I think my claim (based on facebook message from probably a fake account) was proved incorrect. They gave the prizes! (atleast can confirm I got it)