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You might run out of positions for other parity. Try this case

5 4

1 2 3 4 1

Can you explain your dp state ?

How to solve I ?

Logic seems right,may be a bug in implementation

In problem F, How does one get an idea to consider the parity of inversions ? I mean it is not at all obvious to me . If this is a popular idea , can someone give some problems related to it ?


Can anyone give some problems for Segment Tree with Tries,Thanks in Advance