Runtime Error in Almost Sorted Permutation in Python 3 (OCT '15 COOK-OFF)

I was trying the the problem Almost Sorted Permutation which was given in October '15 Cook Off. The problem is pretty straight forward. I just checked if the each no. is at the same index, or one index before, on one index after. Below is the pseudo code:

a = seq of nos. (zero-based index)
if a[0] = 1 or a[1] == 1:
   possible = True
   for i in [1..n-2]:
      if a[i-1] == i+1 or a[i] == i+1 or a[i+1] == i+1:
         possible = False
    if a[n-2] != n or a[n-1] != n:
       possible = False
    if possible == True:
       print 'YES'
       print 'NO'
   print 'NO'    

Link to submitted solution. Please help where the code is getting runtime error.

Because of given sequence isn’t permutation of 1…n

1 Like

@naranbayar I am so stupid. Thanx buddy. :slight_smile: