#check consistency of headline alphabets

#put test alphabets here
a0="T-S-P-U-L--B-EI--CGD------"
a1="K-MOH-N-J--WSU---XZV-D----"
a2="VE----A----N--F-----------" #global
#a2="--E-V-A-------F--N--------"#grocer
#a2="--E-V-A-X----KF--N--------" #grocer ..ing
a3="--------------------------"
#a3="O--TQ---------------------" #dead
#a3="-------------O----T-Q-----" #suns
a4="--------------------------"
EMPTY = 26
period = 5 #room for 5 headlines
symbols = "abcdefghijklmnopqrstuvwxyz-"
def convert_alpha(data):
  data = data.lower()
  alpharow = [symbols.index(c) 
	 for c in data if c in symbols]
  return alpharow
#initialize alpha array and its inverse
alpha = [ [] ] * period
inverse_alpha = [[]]*period
#convert the test alphabets
alpha[0] = convert_alpha(a0)
alpha[1] = convert_alpha(a1)
alpha[2] = convert_alpha(a2)
alpha[3] = convert_alpha(a3)
alpha[4] = convert_alpha(a4)
#set up inverses
for row in range(period):
 inverse_alpha[row]=[EMPTY]*26
 for n in range(26):
  c = alpha[row][n]
  if c != EMPTY:
     inverse_alpha[row][c]=n	 		
def complete_the_squares():
 change_flag = 0
 for r1 in range(period):
  for c1 in range(26):
   c2 = alpha[r1][c1]
   if c2 != EMPTY:
    for r2 in range(period):
     if r1 == r2 : continue
     # vertical extension
     c3 = inverse_alpha[r2][c1]
     if c3 != EMPTY:
      c4 = alpha[r1][c3]
      if c4 != EMPTY:
       c5 = alpha[r2][c4]
       if c5 != EMPTY and c5 != c2:
       	print "Alphabets Inconsistent!"
       	return 0
       alpha[r2][c4] = c2
       inverse_alpha[r2][c2] = c4
       if c5 == EMPTY: change_flag = 1
     # horizontal extension  
     c4 = alpha[r2][c2]
     if c4 != EMPTY:
      c3 = inverse_alpha[r1][c4]
      if c3 != EMPTY:
       c5 = alpha[r2][c1]
       if c5 != EMPTY and c5 != c3:
       	print "Alphabets Inconsistent!"
       	return 0
       alpha[r2][c1] = c3
       inverse_alpha[r2][c3] = c1
       if c5 == EMPTY: change_flag = 1
 return change_flag
#main loop 
flag = complete_the_squares()
while flag != 0:
	flag = complete_the_squares()
print "Consistency check complete"