#Encoding:
- use: "encoding.cpp"
- input: "en-input.dat"
- key: from keyboard
- output: "en-output.dat"
#Decoding:
- use: "decoding.cpp"
- input: "en-output.dat"
- key: from keyboard
- output: "de-output.dat"
#-------------------- just sub,add,mod (- + %) to do this problem.