I don’t know why people make two I’d for them. Is that a backup? If backup then, backup for what?
Here are the links:
https://www.codechef.com/viewsolution/24836276
https://www.codechef.com/viewsolution/24840831
https://www.codechef.com/viewsolution/24840358
https://www.codechef.com/viewsolution/24552815
https://www.codechef.com/viewsolution/24840426
https://www.codechef.com/viewsolution/24648890
https://www.codechef.com/viewsolution/24840488
https://www.codechef.com/viewsolution/24690698
And many more such links? I think this will be easiest for Codechef MOSS. Please do not do such things guys.