[foobarbecue]

Links to programming-challenges.com , which is down, as is the listed backup site. Is there any point in this without that?

[nafizh]

The back up is actually this website:

https://uva.onlinejudge.org/

[romwell]

Use the following websites for problem sets:

[1] https://uva.onlinejudge.org/

[2] https://icpcarchive.ecs.baylor.edu/