// output of ./demo/graph/graph-perm-pref-rev-demo.cc:
// Description:
//% Permutations by prefix reversals.

arg 1: 4 == n  [Permutations of n elements]  default=4
arg 2: 1 == maxnp  [stop after maxnp paths (0: never stop)]  default=1

0:
   0:    0:  [ 0 1 2 3 ]
   1:    1:  [ 1 0 2 3 ]  2
   2:    2:  [ 2 0 1 3 ]  3
   3:    4:  [ 0 2 1 3 ]  2
   4:    5:  [ 1 2 0 3 ]  3
   5:    6:  [ 2 1 0 3 ]  2
   6:    3:  [ 3 0 1 2 ]  4
   7:    8:  [ 0 3 1 2 ]  2
   8:    9:  [ 1 3 0 2 ]  3
   9:    7:  [ 3 1 0 2 ]  2
  10:   12:  [ 0 1 3 2 ]  3
  11:   13:  [ 1 0 3 2 ]  2
  12:   10:  [ 2 3 0 1 ]  4
  13:   11:  [ 3 2 0 1 ]  2
  14:   16:  [ 0 2 3 1 ]  3
  15:   14:  [ 2 0 3 1 ]  2
  16:   15:  [ 3 0 2 1 ]  3
  17:   20:  [ 0 3 2 1 ]  2
  18:   17:  [ 1 2 3 0 ]  4
  19:   18:  [ 2 1 3 0 ]  2
  20:   19:  [ 3 1 2 0 ]  3
  21:   21:  [ 1 3 2 0 ]  2
  22:   22:  [ 2 3 1 0 ]  3
  23:   23:  [ 3 2 1 0 ]  2

n = 4   #pfct = 1
   #paths = 1   #cycles = 1