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Problems with strings and spaces

Fedelway (13)
Hello,

I've been trying to program a simple encryptor but i have some problems with the C-strings and spaces, can you help me find the mistake, because i can't.
When i try to encrypt sentences with several words it only work with the first one and leaves the rest untouched.

Below i leave you the code.

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int main()
{
    char s[100];                //Vector que contendrá a la cadena a encriptar
    char a;                     //Caracter para opciones

    cout << "ingrese una palabra o palabra que desee encriptar (100 caracteres maximo):" << endl;
    cin.getline(s, 100);

    cout << endl
        << "Elija con que metodo quiere encriptarla:" << endl
        << "a) Encriptador del Cesar." << endl
        << "b) Cifrado Atbash." << endl;

    do{
        cin >> a;

        if (a != 'a' && a != 'b')
        {
            cout << "Opcion incorrecta, vuelva a intentar." << endl << endl;
        }
    }while(a != 'a' && a != 'b');

    if (a == 'a')
    {
        Encriptar_cesar(s);
        cout << s << endl << endl
        << "Desea recuperar su cadena(a) o salir del programa directamente(b)?" << endl;
        do{
            cin >> a;
            if (a != 'a' && a != 'b')
            {
                cout << "Opcion incorrecta, vuelva a intentar." << endl;
            }
            if (a == 'a')
            {
                Desencriptar_cesar(s);
                cout << s;
                return 0;
            }
            if (a == 'b')
            {
                return 0;
            }

        }while(a!='a' && a!='b');
    }



Here is the function that does the encryptation:
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  void Encriptar_cesar(char s[])
{
    int i = 0;
    bool f = false;
    while(s[i] != '\0')
    {

        switch (s[i])
        {
            case 'x': s[i]='a';f=true;break;case 'y': s[i]='b';f=true;break;case 'z': s[i]='c';f=true;break;
            case 'X': s[i]='A';f=true;break;case 'Y': s[i]='B';break;f=true;case 'Z': s[i]='C';f=true;break;
            case ' ': f=true; break;
        }

        if(!f)
        {
            s[i] = s[i] + 3;
            f=false;
        }

        i++;
    }
}


I'm from Argentina, so the code is in spanish but i think it's understandable.

Thank you for all your help!
Last edited on
cire (8284)
if (!f) evaluates to true when f is false, so when f is false, you set it to false and when f is true there is no way it can ever become false.
Last edited on
Fedelway (13)
I see...i put the f=false; statement inside the if conditional when it should have been outside. What a stupid mistake :/

Thank you a lot for helping me solve this little problem.
jlb (4973)
I also suggest you clean up your switch statement. Putting so much on one line makes following the logic very difficult. I recommend putting everything on it's own line:

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   switch (s[i])
   {
      case 'x':
         s[i]='a';
         f=true;
         break;
      case 'y':
         s[i]='b';
         f=true;
         break;
      case 'z':
         s[i]='c';
         f=true;
         break;
      case 'X':
         s[i]='A';
         f=true;
         break;
      case 'Y':
         s[i]='B';
         break;
         f=true;
      case 'Z':
         s[i]='C';
         f=true;
         break;
      case ' ':
         f=true;
         break;
   }


Fedelway (13)
I did it that way because the code was getting reaaaally long, and it was annoying to scroll a lot.

In a usual switch i'd do that but here there are lots of cases and very little code in each one, the same in fact. Thanks for the tip, i'm still noob.
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