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procedure generate(k : integer, A : array of any):
if k = 1 then
output(A)
else
// Generate permutations with k-th unaltered
// Initially k = length(A)
generate(k - 1, A)
// Generate permutations for k-th swapped with each k-1 initial
for i := 0; i < k-1; i += 1 do
// Swap choice dependent on parity of k (even or odd)
if k is even then
swap(A[i], A[k-1]) // zero-indexed, the k-th is at k-1
else
swap(A[0], A[k-1])
end if
generate(k - 1, A)
end for
end if