str = input()
for i in str:
if i.islower()==True:
print("{}".format(chr(ord(‘z‘)+ord(‘a‘)-ord(i))),end="")
elif i.isupper()==True:
print("{}".format(chr(ord(‘Z‘)+ord(‘A‘)-ord(i))),end="")
else:
print(i,end="")

字符串反码 A