import random
def randomperm(n):
x = range(n)
for i in xrange(n):
r = random.randint(i,n-1)
(x[i],x[r]) = (x[r], x[i])
return x
if __name__ == "__main__":
import sys
if len(sys.argv) < 2:
print "usage: python randomperm n"
n = int(sys.argv[1])
print randomperm(n)