Caesar's cipher

[Ksenon]

Hello everybody. I've got as homework the coding of Caesar's cipher in C++. I've created the following code. It turns out that the getline function is not working well. Could anyone improve it?

#include <iostream>
#include <string>
using namespace std;
int main()
{
string alphabet= "abcçdeëfghijklmno pqrstuvxyzwABCÇDEËFGHIJKLMNOPQRSTUVXYZW!#$%&'()*+,-./0123456789:;<=>?@[]_{|~}`";
int code[ alphabet.length() ];
for( int j = 0; j < alphabet.length(); j++ )
code[ j ] = j;
cout << "Hello. You can cipher your messages through the following alphabet\n";

for( int c = 0; c < alphabet.length(); c++ )
cout << alphabet[ c ] << ' ';
int continue;
cout << "\nType a number to continue. Press -1 to end: ";
cin >> continue;

while( continue!= -1 )
{
string text;
cout << "Input a message: ";
getline( cin, text);
char cipher[ text.length() ];

int key;
cout << "Input key: ";
cin >> key;
int counter = 0;
for( int i = 0; i < text.length(); i++ )
{
for( int k = 0; k < alphabet.length(); k++ )
{

if( text[ i ] == alphabet[ k ] )
{

cipher[ counter ] = alphabet[ (code[ k ] + key ) % alphabet.length()];
counter++;
}
}
}
if (counter == text.length() )
{
cout << "The cipher text is: ";
for( int l = 0; l < counter; l++ )
cout << cipher[ l ];
}
else
cout << "The preceding text cannot be ciphered" << endl;
cout << "nType a number to continue. Press -1 to end: ";
cin >> continue;
}
}

[MiiNiPaa]

http://stackoverflow.com/questions/21567291/why-does-stdgetline-skip-input-after-a-formatted-extraction

[Ksenon]

It turns out that i should use cin.ignore(). But i don't know where to place it.

[MiiNiPaa]

It turns out that i should use cin.ignore().

No, in your case, it would be way better to use std::ws, as answer by my link indicated;

But i don't know where to place it.

As shown in linked answer, you should place it inside getline (actually between formatted input and getline call)
getline(std::cin >> std::ws, text);

[Ksenon]

Thank you very much. But i've got another problem though. This code that i've created, doesn't cipher these elements: ç, ë, Ç and Ë. Do you have any idea how to fix it?

[MiiNiPaa]

This can be problematic. Those characters are not a part of standard character table. Their representation in your source editor and in console can differ.
You can try saving your source file using same encoding your console uses.