作业8

fr = open('fjq.txt',mode='r',encoding='utf-8')
fjq = fr.read()
print('明文：'+ljy)
print('密文：',end='')

fw = open('cipherText.txt',mode='a',encoding='utf-8')
for c in fjq:
    print(chr(ord(c)+3),end='')
    fw.write(chr(ord(c)+3))

fr.close()
fw.close()

fjq = open('plainText.txt',mode='r', encoding='utf-8')
plainText = fjq.read()
print('明文：'+plainText)
print('密文：',end='')
for c in plainText:
    print(chr(ord(c)+3),end='')


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