字符串及其操作，字符的Unicode编码

plainText=input('message:')
for c in plainText:
    print(chr(ord(c)-3),end='')

　　

plainText=input('message:')
for c in plainText:
    print(chr(ord(c)+3),end='')

　　

for i in range(12):
    print(9800+i,chr(9800+i))