This gives you the number of letters that appear in both words in the same position:
sum(1 for a, b in zip(word1, word2) if a == b)
zip
gives you an iterator for each character in both words at the same time, and you simply sum 1
for each time they match.
This gives you the generally shared letters between both words in any position:
len(set(word1) & set(word2))
This creates two sets of letters, takes the intersection of both sets, and tells you how big that intersection is.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…