defencrypt(str_c):
result =''for i in str_c:if i.islower():
result +=chr((ord(i)-ord('a')+4)%26+ord('a'))elif i.isupper():
result +=chr((ord(i)-ord('A')+4)%26+ord('A'))else:
result += i
return result
defdecrypt(str_a):
result =''for i in str_a:if i.islower():# 这里和C语言不一样, python -3%26 = 23, C语言 -3%26 = -3
result +=chr((ord(i)-ord('a')-4)%26+ord('a'))elif i.isupper():
result +=chr((ord(i)-ord('A')-4)%26+ord('A'))else:
result += i
return result
# print(encrypt('i" laohu you wxyzaa..'))print(decrypt(' ABCD'))