Input
3 3 1
1 1
3 3
Output
0
is it correct?

I think so. My AC solution outputs 0.

It should be noted that the problem statement doesn't mention what happens if you can't get next to the demon in at most L moves. Either such a test is invalid or you should output 0, since you can't stike it, thus you give it a stike of at most 0 intensity.