Python版本

Python 里无法直接对单个字符作差得到ASCII码（Unicode码），所以需要借助 ord 和 chr，或者你能记住 a、A、0 的ASCII码也行……

def crypto(string):
    temp = []
    for c in string:
        if ord('a') <= ord(c) <= ord('z'):
            temp.append(chr((ord(c.upper())-ord('A')+1)%26 + ord('A')))
        elif ord('A') <= ord(c) <= ord('Z'):
            temp.append(chr((ord(c.lower())-ord('a')+1)%26 + ord('a')))
        elif ord('0') <= ord(c) <= ord('9'):
            temp.append(str((int(c)-0+1)%10+0))
        else:
            temp.append(c)
    return ''.join(temp)

def decrypt(string):
    temp = []
    for c in string:
        if ord('a') <= ord(c) <= ord('z'):
            temp.append(chr((ord(c.upper())-ord('A')+25)%26 + ord('A')))
        elif ord('A') <= ord(c) <= ord('Z'):
            temp.append(chr((ord(c.lower())-ord('a')+25)%26 + ord('a')))
        elif ord('0') <= ord(c) <= ord('9'):
            temp.append(str((int(c)-0+9)%10+0))
        else:
            temp.append(c)
    return ''.join(temp)

while True:
    try:
        string_raw = input()
        string_cpt = input()
        print(crypto(string_raw))
        print(decrypt(string_cpt))
    except Exception:
        break