OJ Board

O(n) solution:

Sequence starts at first maximum point (fred, fred>fred[i+1]) (result=2)
after that increase result at each extremum point

I'm trying to solve it in O(n), but don't understand what's wrong with this code
Please help me
subsequence can be not cosequtive

Thank you very much!
I understand it

Thank you
Yes I understand, my way is wrong

So I just should divide on (i-1)
If a or b are odd then 1 else 0 . Am I right?

I broke my head, but didn't invent nothing
Please help me, any hint?

I recieve a and b for each power
1 0
-1 1
0 -2
2 2
-4 0
4 -4
.....

but I don't know what subset we should use for
generation answer?