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  1. def SJTperms(a, dirs):
  2.     n = len(a)
  3.     id = -1
  4.     for i in range(n):
  5.         #   can check mobility           mobile                        largest mobile
  6.         if (0<=i+dirs[i]<n)       and (a[i] > a[i+dirs[i]])     and ((id == -1) or (a[i] > a[id])):
  7.             id = i
  8.  
  9.     if (id == -1):  #last permutation
  10.         return False
  11.  
  12.     for i in range(n):
  13.         if a[i] > a[id]:
  14.             dirs[i] = - dirs[i]
  15.  
  16.     #swap elements AND their directions
  17.     a[id], a[id + dirs[id]] = a[id + dirs[id]], a[id]
  18.     t = dirs[id]
  19.     dirs[id], dirs[id + t] = dirs[id + t], dirs[id]
  20.     return True
  21.  
  22. a = [1,2,3,4]
  23. d = [-1]*len(a)
  24. cont = True
  25. while cont:
  26.     print(a)
  27.     #print(d)
  28.     cont = SJTperms(a, d)
Success #stdin #stdout 0.02s 9036KB
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stdin
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Standard input is empty
stdout
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[1, 2, 3, 4]
[1, 2, 4, 3]
[1, 4, 2, 3]
[4, 1, 2, 3]
[4, 1, 3, 2]
[1, 4, 3, 2]
[1, 3, 4, 2]
[1, 3, 2, 4]
[3, 1, 2, 4]
[3, 1, 4, 2]
[3, 4, 1, 2]
[4, 3, 1, 2]
[4, 3, 2, 1]
[3, 4, 2, 1]
[3, 2, 4, 1]
[3, 2, 1, 4]
[2, 3, 1, 4]
[2, 3, 4, 1]
[2, 4, 3, 1]
[4, 2, 3, 1]
[4, 2, 1, 3]
[2, 4, 1, 3]
[2, 1, 4, 3]
[2, 1, 3, 4]
https://ideone.com/67U2us
language:
Python 3 (python  3.12)
created:
4 years ago
visibility:
public

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