1111

abc = 'АБВГДЕЖЗИКЛМ'

s = 'АБВГД БВЕ ВГЖ ГДЖ ДЖЗ ЕВЖИ ЖИ ЗЖИ ИКЛ КМ ЛКМ'
s = s.split(' ')
sour = {c:set() for c in 'АБВГДЕЖЗИКЛМ'}
dest = {}
for word in s:
    dest[word[0]] = word[1:]
    for letter in word[1:]:
        sour[letter].add(word[0])

print(sour)
print(dest)

path = 'БЕВГДЗЖИЛКМ'
paths = {c : dict() for c in 'АБВГДЕЖЗИКЛМ'}
paths['А'][0] = 1
for v in path:
    for vs in sour[v]:
        for length, n_paths in paths[vs].items():
            paths[v][length+1] = paths[v].get(length+1, 0) + n_paths
print()
print(paths)