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@vznvzn
Created June 12, 2015 22:36
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def dense(n)
s = n.to_s(2)
c = 0
s.length.times \
{
|i|
c += s[i, 1].to_i
}
return c.to_f / s.length
end
def f(n)
n1 = n
c = 0
m = 0
while (n != 1 && n >= n1)
n = n * 3 + 1 if (n.odd?)
n /= 2 while (n.even?)
m = [m, n].max
c += 1
end
return {'w' => widthdiff(m, n1), 'c' => c, 'd' => (0.5 - dense(n1)).abs}
end
def long(m)
l = [{'n' => 1, 'p' => 0}.merge(f(1))]
loop \
{
l = l.sort_by { |x| [x['w'], x['d']] }.reverse
break if (l[0]['w'] >= m)
x = l.delete_at(rand([l.size, 2].min))
p2 = x['p'] + 1
n2 = x['n'] + 2 ** p2
x1 = x.dup
x1['p'] = p2
l << x1
x2 = {'n' => n2, 'p' => p2}.merge(f(n2))
l << x2
}
l.sort_by! { |x| -x['c'] }
return l.first, l.size
end
def widthdiff(a, b)
a.to_s(2).length - b.to_s(2).length
end
def two(p)
x, c = long(p)
a = x['n']
a1 = a
ns = a.to_s(2)
b = ('1' + ns[2..-1]).to_i(2)
b1 = b
mx = ma = mb = 0
m = nil
while (b != 1 && b >= b1)
a = a * 3 + 1 if (a.odd?)
a /= 2 while (a.even?)
b = b * 3 + 1 if (b.odd?)
b /= 2 while (b.even?)
m = widthdiff(a, b).abs
mx = [m, mx].max
ma = [a, ma].max
mb = [b, mb].max
end
return mx, widthdiff(ma, a1), widthdiff(mb, b1), c
end
(1..1000).each \
{
|p|
puts([p, two(p)].join("\t"))
$stdout.flush
}
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