Having at last had a go at solving this, post breakfast (if not Brexit).
I don't think it's a new approach, but it's fairly nifty.
It considers run lengths times heights.
a =: >./^:2@:(>:@i.@# ([ * <./\) ])
qq=:1000?.1000000
a qq
7030779
ts'a qq' NB. time & space
0.0328879 2.24246e7
ts'maxsqr qq'
0.0385574 322944
So - marginally faster, but rather space intensive.
Probably better with a stopping condition, perhaps using ^:_ , rather than
doing all possible heights, but the code would be a bit more
complicated, I think.
Cheers,
Mike
On 21/06/2017 14:12, Raul Miller wrote:
nsqr=: [ * maxbitlen@ceilpos"0 1~
maxsqr=: >./@(nsqr ~.)
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