Do your own homework, dude. I'll give you a little hint.

#include <fstream>
using namespace std;

int main()
{
ifstream infile("indata.txt", ios::in | ios::binary);
ofstream outfile("outdata.txt", ios::out || ios::binary);
char temp;

while(infile)
{
infile.get(temp);
__asm
{
mov bl, temp
rol bl, 3
mov temp, bl
}
outfile.put(temp);
}

infile.close();
outfile.close();
}

That's the encryption part. use ror operator for decryption part. good luck.

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