fib =. monad define M.
	if. y<:2 do.
		x:1
	else.
		(fib y-1) + fib y-2
	end.
)
digits =. #&":
solve =. monad define
	n =. 1
	f =. 0
	whilst. y > digits f do.
		n =. >: n
		f =. fib n
	end.
	n
)
problem25 =: solve 1000