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It is really strange that I got lots of 'Runtime error' even if my Java code reads in the input data without doing anything.
It works for me, two possible problems I can think of:
1) As was written earlier in this thread, the input is terminated by EOF, not by 0 0!
2) If you use scanner.nextInt or ...

Hello,
can anyone give me a hint how to solve this problem effectively?

Here's what I tried:

For the 840 possible states I calculated the adjacency matrix.
Then I used matrix multiplication to precalculate the number of paths of length 2^1 ... 2^30 from each state to each state.

Then for each ...

Yeah, I had the same problems with Java on that one.
I spent about 2 hours trying to optimize my solution, but kept getting TLE, until i finally realized it timed out because just reading the input would already take more than 2 seconds.

But the problem is still solvable using Java, after I used ...