Danny Code

#include <iostream>
#include <string>

using namespace std;

string danny_code(string);

int main() {

    string str;

    cout << "Enter sentence to encrypt: ";
    getline(cin, str);

    string encrypted = danny_code(str);

    cout << "\n\nEncrypted: " << danny_code(str);
    cout << "\n\nDecrypted: " << danny_code(encrypted);

    return 0;
}

string danny_code(string str) {

    char key[5] = { 'D', 'A', 'N', 'N', 'Y' };

    string result = str;

    for (size_t i = 0; i < str.length(); i++)
        result[i] = str[i] ^ key[i % (sizeof(key) / sizeof(char))];

    return result;
}