Given an arbitrary sequence of numbers, for example
a=: 1 1 1 3 3 3 4 4 4 3 3 3 5 5 5 2 2 1 1 1
and a some related arbitrary bit vector (except that the
last bit must be 0), for example
b=: ?.2#~#a
Find the smallest indices c such that
c *./ .> I.b
c *./ .<:&({&a) I.b
thus, if
b=:(i.#a) e. 1 2 5 7 12 14
in the above example,
c=: 2 17 9 8 13 15
Values of b where c can not exist (for example, if the last
bit in b is a 1) should cause an error.
example=:4 :0 NB. a example b
c=.1+I.y
while.1 e. s=.c >&({&x) I.y do.
c=.c+s
end.
c
)
A=: 0,~ ([EMAIL PROTECTED])(-<./)+/\<:?.1e3#3
B=: 0,~?.2#~<:#A
(6!:2,7!:2) 'A example B'
0.306458 149824
Can you do better than this?
--
Raul
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