// output of ./demo/perm/permrand-derange-demo.cc:
// Description:
//% Random derangements (permutations with no fixed points)

arg 1: 10 == n  [Number of elements.]  default=10
arg 2: 15 == rep  [This many derangements.]  default=15
   f=[ 8 9 7 2 6 4 1 0 3 5 ]    (0, 8, 3, 2, 7) (1, 9, 5, 4, 6)         
   f=[ 1 4 5 6 7 8 2 0 9 3 ]    (0, 1, 4, 7) (2, 5, 8, 9, 3, 6)         
   f=[ 9 5 1 2 6 7 4 3 0 8 ]    (0, 9, 8) (1, 5, 7, 3, 2) (4, 6)        
   f=[ 5 3 9 4 0 2 8 1 6 7 ]    (0, 5, 2, 9, 7, 1, 3, 4) (6, 8)         
   f=[ 5 3 8 4 7 9 2 0 1 6 ]    (0, 5, 9, 6, 2, 8, 1, 3, 4, 7)          
   f=[ 1 2 3 5 8 7 0 4 9 6 ]    (0, 1, 2, 3, 5, 7, 4, 8, 9, 6)          
   f=[ 8 6 9 1 5 0 7 2 4 3 ]    (0, 8, 4, 5) (1, 6, 7, 2, 9, 3)         
   f=[ 5 0 9 4 8 7 2 1 3 6 ]    (0, 5, 7, 1) (2, 9, 6) (3, 4, 8)        
   f=[ 7 0 6 2 3 9 5 1 4 8 ]    (0, 7, 1) (2, 6, 5, 9, 8, 4, 3)         
   f=[ 6 0 9 4 5 7 3 8 1 2 ]    (0, 6, 3, 4, 5, 7, 8, 1) (2, 9)         
   f=[ 8 0 7 6 2 9 4 3 1 5 ]    (0, 8, 1) (2, 7, 3, 6, 4) (5, 9)        
   f=[ 9 7 8 2 3 6 5 0 1 4 ]    (0, 9, 4, 3, 2, 8, 1, 7) (5, 6)         
   f=[ 2 4 8 0 5 6 7 9 1 3 ]    (0, 2, 8, 1, 4, 5, 6, 7, 9, 3)          
   f=[ 6 7 4 9 0 1 5 8 3 2 ]    (0, 6, 5, 1, 7, 8, 3, 9, 2, 4)          
   f=[ 1 4 8 0 6 7 3 2 9 5 ]    (0, 1, 4, 6, 3) (2, 8, 9, 5, 7)         
