Verschlüsselung (mit comment)

//--------------------------------------------------------------------------//
#include <iostream>                                                         //
#include <fstream>
#include <string>                                                           //
//--------------------------------------------------------------------------//
using namespace std;                                                        //
//--------------------------------------------------------------------------//
int main()
{
    string n , n2 , n3 , s = "" , s2 = "" , s3 = "" , t = "" , q;
    int key1 = 13, key2 = 5, key3 = 7;

    cout << "----------:Please Enter Something:----------" << endl << endl;
    cout << "____________________________________________\n" << endl;
    cout << "Bitte zu Verschluesselnden Text eingeben" << endl;
    cout << "Eingabe: ";
    getline( cin , n );
    cout << endl;
    cout << "Bitte Key Eins eingeben (Nur Zahlen)" << endl;
    cout << "Eingabe: ";
    cin >> key1;
    cout << endl;
    cout << "Bitte Key Zwei eingeben (Nur Zahlen)" << endl;
    cout << "Eingabe: ";
    cin >> key2;
    cout << endl;
    cout << "Bitte Key Drei eingeben (Nur Zahlen)" << endl;
    cout << "Eingabe: ";
    cin >> key3;
    cout << endl;

    //Verschlüsselung 1
    int l = n.length( );
    for( int i = 0 ; i < l ; i++ )
    {
        if( n[i] == ' ' )
        {
            s = s+" ";
            continue;
        }
        if( n[i] >= 'A' && n[i] <= 'Z' )
        n[i] += 32;
        if( n[i] >= 'm' && n[i] <= 'z' )
        {
            char a = 'z' , b = 'a';
            int k = ( int ) a - ( int ) n[i];
            n[i] = char ( ( int ) b + ( key1 - k - 1 ) );
        }
        else
        {
            n[i] = char ( ( int ) n[i] + key1 );
        }
        s = s + n[i];
    }

    //Verschlüsselung 2
    int l2 = s.length( );
    for( int i = 0 ; i < l2 ; i++ )
    {
        if( s[i] == ' ' )
        {
            s2 = s2+" ";
            continue;
        }
        if( s[i] >= 'A' && s[i] <= 'Z' )
        s[i] += 32;
        if( s[i] >= 'm' && s[i] <= 'z' )
        {
            char a = 'z' , b = 'a';
            int k = ( int ) a - ( int ) s[i];
            s[i] = char ( ( int ) b + ( key2 - k - 1 ) );
        }
        else
        {
            s[i] = char ( ( int ) s[i] + key2 );
        }
        s2 = s2 + s[i];
    }

    //Verschlüsselung 3
    int l3 = s2.length( );
    for( int i = 0 ; i < l3 ; i++ )
    {
        if( s2[i] == ' ' )
        {
            s3 = s3+" ";
            continue;
        }
        if( s2[i] >= 'A' && s2[i] <= 'Z' )
        s2[i] += 32;
        if( s2[i] >= 'm' && s2[i] <= 'z' )
        {
            char a = 'z' , b = 'a';
            int k = ( int ) a - ( int ) s2[i];
            s2[i] = char ( ( int ) b + ( key3 - k - 1 ) );
        }
        else
        {
            s2[i] = char ( ( int ) s2[i] + key3 );
        }
        s3 = s3 + s2[i];
    }
    cout << "Encrypted: " << s3 << endl;

    //system("cls");                                                            //
    cout << "\n";                                                           //
    cout << "\n";                                                           //
    cout << "\n";                                                           //
    ofstream myfile;                                                        //
    myfile.open ("example.txt");                                            //
    myfile << s3;                                                           //
    myfile.close();                                                         //
    system("PAUSE");                                                        //
    return 0;                                                               //
}                                                                           //
//--------------------------------------------------------------------------//
/*  cout << "Bitte erneut eingeben: ";
    cin >> q;
    int l2 = q.length( );
    cout << "String laenge: " << l2 << endl;

    for( int p = 0 ; p < l2 ; p++ )
    {
        cout << t << " ";
        switch( q [ p ] )
        {
            case 'a':
            case 'A':
            t[p] = '1';
            break;

            case 'b':
            case 'B':
            t[p] = '2';
            break;

            case 'c':
            case 'C':
            t[p] = '3';
            break;

            case 'd':
            case 'D':
            t[p] = '4';
            break;

            case 'e':
            case 'E':
            t[p] = '5';
            break;

            case 'f':
            case 'F':
            t[p] = '6';
            break;

            case 'g':
            case 'G':
            t[p] = '7';
            break;

            case 'h':
            case 'H':
            t[p] = '8';
            break;

            case 'i':
            case 'I':
            t[p] = '9';
            break;

            case 'j':
            case 'J':
            t[p] = '10';
            break;

            case 'k':
            case 'K':
            t[p] = '11';
            break;

            case 'l':
            case 'L':
            t[p] = '12';
            break;

            case 'm':
            case 'M':
            t[p] = '13';
            break;

            case 'n':
            case 'N':
            t[p] = '14';
            break;

            case 'o':
            case 'O':
            t[p] = '15';
            break;

            case 'p':
            case 'P':
            t[p] = '16';
            break;

            case 'q':
            case 'Q':
            t[p] = '17';
            break;

            case 'r':
            case 'R':
            t[p] = '18';
            break;

            case 's':
            case 'S':
            t[p] = '19';
            break;

            case 't':
            case 'T':
            t[p] = '20';
            break;

            case 'u':
            case 'U':
            t[p] = '21';
            break;

            case 'v':
            case 'V':
            t[p] = '22';
            break;

            case 'w':
            case 'W':
            t[p] = '23';
            break;

            case 'x':
            case 'X':
            t[p] = '24';
            break;

            case 'y':
            case 'Y':
            t[p] = '25';
            break;

            case 'z':
            case 'Z':
            t[p] = '26';
            break;

            default:
            t[p] = '27';
            break;
        }
    }

    cout << t << endl;*/

    //a = 1 -> Z = 26
    //cout << a << " ";