love_letter_mystery.py 文件源码

def get_num_ops(s):
    if s == s[::-1]:
        return 0
    else:
        list_s = list(s)
        alph = string.lowercase
        len_s = len(s) 
        index = 0
        num_ops = 0
        while index < len_s:
            if s[index] != s[(len_s - 1) - index]:
                if s[(len_s - 1) - index] > s[index]:
                    list_s[(len_s - 1) - index] = list_s[index]
                else:
                    list_s[index] = list_s[(len_s - 1) - index]
                num_ops += abs(alph.find(s[(len_s - 1) - index]) - alph.find(s[index]))
            index += 1
        return num_ops / 2