Program C++ Deskripsi dan Enskripsi

Algoritma :

{ Mengenskripsi karakter yang diinput dan mendeskripsikannya kembali }

Deklarasi

key                                   : integer

plain, chipper, teks           : char

Deskripsi

read(key,plain)

for i <= 0 to strlen(plain) do

plain[i](int (plain[i]))

chipper[i] = (plain[i] + key) % 128

for i<= 0 to strlen(chiper) do

teks[i] = (chiper[i] – key) % 128

endfor

endfor

write(chipper,teks)

Berikut kode programnya :

#include <cstdlib>

#include <iostream>

using namespace std;

class geser{

      public:

             friend istream& operator>>(istream&, geser&);

             friend ostream& operator<<(ostream&, geser&);

             void enkripsi();

             void deskripsi();

      private:

              char plain[128], chiper[128], teks[26];

              int key;

              };

      istream& operator>>(istream& in, geser& a){

               cout<<"Masukkan key = ";

               in>>a.key;

               cout<<"Masukkan karakter = ";

               in>>a.plain;

               return in;

               }

      void geser::enkripsi(){

           for(int i=0; i<strlen(plain); i++){

                   cout<<plain[i]<<"("<<int(plain[i])<<")";

                   chiper[i]=(plain[i]+key)%128;

                   }

                   }

      void geser::deskripsi(){

           for (int i=0; i<strlen(chiper); i++){

               teks[i]=(chiper[i]-key)%128;                                

               }

               }

      ostream& operator<<(ostream& out, geser& b){

               out<<"Hasil Enkripsi :"<<endl;

               for(int i=0; i<strlen(b.plain); i++){

                   out<<b.chiper[i];

                   }

               out<<endl;

               out<<"Hasil Deskripsi :"<<endl;

               for(int j=0; j<strlen(b.chiper); j++){

                   cout<<b.teks[j];

                   }

                   return out;

                   }        

int main(int argc, char *argv[])

{

    geser x;

    cin>>x;

x.enkripsi();

x.deskripsi();

    cout<<endl;

    cout<<x;

    cout<<endl;

    system("PAUSE");

    return EXIT_SUCCESS;

}

explanation:

In the above program is a program that is used for encryption and description of a character. With this program we can use it mengenkrips code that we make. Which one has the following formula:
Enskripsi: cipher = (plain + key)% 128
Deskripsi: teks = (cipher - key)% 128
In the above program using this type of for loop, to input the key and the characters will be encrypted and to describe again.