These 3 people belong to the same college and have been involved in plagiarism since a past few months.
For the first problem of cookoff,all three have the exact same code .
Link to the submission(s):-
https://www.codechef.com/viewsolution/23664212
https://www.codechef.com/viewsolution/23664339
Codechef admins, I request you to look into this matter.
WOW !!! How do you guys find all these solutions? Do you read each and every code one by one?
And yes, they’ll surely be caught during the MOSS check.
According to me, MOSS check is not that strong thats why they have not been caught even after doing-3-months-of plagiarism.
Thats why I am reporting it to admins @vijju123
I am one of their acquaintance. Always had a doubt on them. So kept a keen eye for detail 
MOSS is not too weak. In this case, they just changed the variable but the structure of code remains as it is that is were MOSS comes into the role. And they will be definitely penalized.