RosettaCodeData/Task/Superpermutation-minimisation/Julia/superpermutation-minimisation.jl
2024-10-16 18:07:41 -07:00

40 lines
834 B
Julia

const nmax = 12
function r!(n, s, pos, count)
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, pos, count) == 0
return false
end
end
s[pos + 1] = c
pos += 1
true
end
function superpermutation(n)
count = zeros(nmax)
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, pos, count) ; end
superperm
end
function testsuper(N, verbose=false)
for i in 0:N-1
s = superpermutation(i)
println("Superperm($i) has length $(length(s)) ", (verbose ? String(s) : ""))
end
end
testsuper(nmax)