{{{~cpp 

#include <fstream>  
#include <iostream> 
using namespace std;  
  
int main()  
{  
        ifstream fin("source.txt");
		ofstream fout("output.txt");
	//	ofstream fout2("result.txt");
  
        char a;  
        int key; 
        cout << "key 를 입력하세요(단,숫자) : "; 
        cin >> key; 
 
        while(fin>>a) 
        { 
   
		   fout << (char)((int)a+key);
		   cout << (char)((int)a+key);
        }
		

        cout << "암호와 완료..해석불능..\n"; 
        return 0;  
}  
}}}

아...야메....
반대로.실패함...야메는 야메일뿐..