A hint, if you will: All solutions that ya'll tryn'na google are incorrect. Bruteforcing using itertools is not going to work at all.

A better hint: try to solve this by intelligently counting derangements and partial derangements.

can anyone please help me with the probability explanation??

Who is here becaue of George Hotz??

Still did not understand how 89/315 % 109 + 123 = 498412760. Can somebody explain?

Didn't get question!