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def solve(a):
steps = 0
sol = range(1,len(a)+1)
# stop if solved
while a != sol:
try:
print "%s not sorted" % a
# first flip all pairs
for i in range(len(a)):
if a[i] != i+1 and a[a[i]-1] == i+1:
print 'PAIR FLIP %d and %d' % (a[a[i]-1], a[i])
t = a[a[i]-1]
a[a[i]-1] = a[i]
a[i] = t
steps += 2
raise Exception
# now find the first mixed index to fix
for i in range(len(a)):
if a[i] != i+1:
print 'FLIP %d and %d' % (a[a[i]-1], a[i])
t = a[a[i]-1]
a[a[i]-1] = a[i]
a[i] = t
steps += 2
raise Exception
except:
continue
assert steps <= (len(a)-1)*2 # upper bound
return steps
f = open('2.in', 'r')
o = open('2.out', 'w')
T = int(f.readline().strip())
for t in xrange(T):
_n = f.readline().strip()
el = map(int, f.readline().strip().split(' '))
print el
res = solve(el)
s = "Case #%d: %s\n" % (t+1, res)
print s
o.write(s)
f.close()
o.close()
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