k=0 
 for i1 in 'ae': 
     for i2 in 'ae': 
         for i3 in 'dcb': 
             for i4 in 'dcb': 
                 s=i1+i2+i3+i4 
                 k+=1 
 print(k) 
  
  
 

 
 k=0 
 for i1 in 'aedcb': 
     for i2 in 'aedcb': 
         for i3 in 'aedcb': 
             for i4 in 'aedcb': 
                 s=i1+i2+i3+i4 
                 if s.count('ea')==0 and s.count('de')==0 and s.count('cd')==0 and s.count('bc')==0 and s.count('da')==0 and s.count('bd')==0 and s.count('ce')==0 and s.count('ca')==0 and s.count('be')==0 and s.count('ba')==0: 
                     k+=1 
 print(k) 
  
  
 

 
 from itertools import product 
  
 a = list(product('ABCDE', repeat=4)) 
 n = 0 
 for el in a: 
     ell = list(el) 
     if ell == sorted(ell): 
         print(el) 
         n += 1 
 print(n) 
 

 
 from itertools import combinations_with_replacement 
 a = list(combinations_with_replacement('ABCDE', 4)) 
 print(len(a)) 
 

 
 from itertools import product 
  
 words = set(("".join(sorted(w)) for w in product('ABCDE', repeat=4))) 
 print(words)