Atbas Encryption

#include <iostream>
#include <string>
#include <vector>
#include <map>
#include <algorithm>

using namespace std;

// Helpful Functions
void displayVector(vector <char> v){
    for(unsigned int i=0; i<v.size(); i++){
        cout << v[i] << endl;
    }
}


void displayMap(map <char,char> myMap){
    map <char,char> :: iterator mitr;
    for(mitr=myMap.begin(); mitr!=myMap.end(); mitr++){
        cout << "Key: " << mitr->first << "    Value: " << mitr->second << endl;
    }
}

int main()
{
    // 1. Intro
    cout << "This programme is about the famous code 'Atbas'.\n";

    //2. Create the vectors that contains all the letters of Alphabets
    vector <char> alphabet = vector <char> ();
    vector <char> alphabetReversed = vector <char> ();
    for(char c='a'; c<='z'; c++){
        alphabet.push_back(c);
    }

    // 3. Create the 2'Atbas' maps: first for ciphering and the other one for deciphering
    // Encryption
    map <char,char> atbasEncryption = map <char,char> ();
    map <char,char> atbasDecryption = map <char,char> ();

    for(unsigned int i=0; i<alphabet.size(); i++){
        atbasEncryption.insert({alphabet[i],alphabet[alphabet.size()-1-i]});
    }

    cout << "Write the message you want me to cipher:\n";
    string message;
    getline(cin, message);
    string answer;

    if(message.size() == 0){
        cout << "With 0 letters, what do you expect from me to do?" << endl << endl;
        return 0;
    }
    else{
        for(unsigned int i=0; i<message.size(); i++){
            if(message[i] == ' '){
                answer += ' ';
            }
            else{
                answer += (atbasEncryption.find(message[i])->second);
            }
        }
        cout << "Message before:    " << message << endl;
        cout << "Message encrypted: " << answer << endl;
    }

    return 0;
}