I keep getting non-zero return from WA #9 (meaning some of my scanf() fails)
Could you please forward WA #9 problem so that I can check parsing is proper?
Thank you,

Test #9 probably contains upper limit case, when there are max possible levels with max planets in each, I can suggest you to check your array sizes. I also got WA #9 after setting wrong integer value for "unreachable" planets - I've set it too small and it affected the result at this test

You're right...
After changing the values to a higher value for the unreachable nodes, I got AC.
Thanks.