Superpermutation minimisation: Difference between revisions

=={{header|Julia}}==

{{trans|D}}

<lang julia>const nmax = 12

function superpermutation(n)

pos = 1

count = zeros(nmax)

function r!(n, s)

if n == 0

return false

end

c = s[pos + 1 - n]

count[n + 1] -= 1

if count[n + 1] == 0

count[n + 1] = n

if r!(n - 1, s) == 0

return false

end

end

s[pos] = c

pos += 1

return true

end

pos = n

superperm = zeros(UInt8, n < 2 ? n : mapreduce(factorial, +, 1:n))

for i in 0:n-1

count[i + 1] = i

superperm[i + 1] = Char(i + '0')

end

count[n + 1] = n

while r!(n, superperm) ; end

String(superperm)

end

function testsuper(N, verbose=false)

for i in 0:N-1

s = superpermutation(i)

println("Superperm($i) has length $(length(s)) ", (verbose ? s : ""))

end

end

testsuper(nmax)

</lang>{{out}}

<pre>

Superperm(0) has length 0

Superperm(1) has length 1

Superperm(2) has length 3

Superperm(3) has length 9

Superperm(4) has length 33

Superperm(5) has length 153

Superperm(6) has length 873

Superperm(7) has length 5913

Superperm(8) has length 46233

Superperm(9) has length 409113

Superperm(10) has length 4037913

Superperm(11) has length 43954713

</pre>